A Guide to (Modern) Etiquette....according to Mr JHM Walsh

What's the best way to avoid getting mugged? When should you not leave a tip, or send a dish back? How do you compliment your friend on their plastic surgery? How do you exit, gracefully, after a one-night stand? modern life can be confusing, but John Walsh has the answers to these thorny questions - and many more

Street Life

Why do some people take ages at a cashpoint, and what is the correct way of encouraging them to get a move on?

Nobody knows what these people are doing. If they're not taking out money or checking their bank balance, are they a) booking their holiday, b) playing some complicated form of computer Sudoku or c) tracking al-Qa'ida operatives through a sophisticated satellite network? It's impossible to say. But once five minutes have elapsed, the only course of action is to seize the miscreant by the hair and slam his face into the computer screen.

How should one dress so as not to get mugged?

If you're a man, dress like Grayson Perry, complete with doll, pigtails, clumpy high heels and adorable yellow bow. This works best if you're over six feet tall to start with. If you're a woman, pump up your chest to huge proportions, acquire a face mask so as to resemble Lea from the current Big Brother, and even the most desperate villain will give you a wide berth.

How should women retaliate when beeped at by young admirers in cars and white vans?

Expressions of admiration from the male sex to the fair sex take many forms, of which the hooting of car horns is perhaps not the most sophisticated. It may be a cry for help. It may be, as TS Eliot expressed it, "a raid on the inarticulate/ with shabby equipment". It is up to you whether to take up the implied offer of a short but invigorating physical relationship, or to locate a box of eggs in your shopping and fling them at the bastard's windshield.

Eating & Drinking

How much does one tip in a restaurant these days, and under what circumstances does one not tip?

It depends. In Burger King or Pret a Manger, you tip nothing. In the Pizza Express or Wagamama, you bung the waiter 10 per cent. In practically all urban restaurants where a meal costs £50 for two, you should tip a bit more - but the management will almost certainly sling an "optional" 12.5 per cent on the bill. Don't take it off just because the roast potatoes were burnt; it wasn't the waiter's fault. In posher restaurants (£100 for two or more) they may screw you for 15 per cent, which you're entitled to revise downwards if the service was less than fawning. In New York eating circles, diners usually tip 20 per cent, which is obviously ridiculous.

One refuses to tip anything at all on rare occasions, eg if you've had to query the bill several times, or the waiter has raised his eyes heavenwards when asked to explain the words cromesquis or velouté.

In what circumstances can you send back a dish/ a bottle of wine?

You can send back a dish if it's undercooked, on the grounds that it may be injurious to health. Ditto if it's overcooked, provided you specified how you wanted it. You can not send it back "because it doesn't taste nice" for fear that the management may laugh at you, nor complain that "it doesn't taste of anything", in case they bring you bottles of tomato ketchup, HP Sauce, Tabasco etc, in a satirical swipe at your insensitive taste buds.

You can reject a bottle of wine if it's a different year from the vintage promised on the carte des vins. You're invited to "try" it only to establish whether or not it's corked (ie the cork is contaminated with the TCA fungus and the wine smells like a cellarful of musty cardboard) and you can reject it if such is the case. If you ordered a sauternes to accompany the beef, the waiter should have advised you against such a blunder. If you ordered côtes du rhône thinking it would taste like châteauneuf-du-pape, well that was pretty dumb but you can't complain now.

What is the ideal dining arrangement for 10 friends celebrating a birthday?

There's a dwindling enthusiasm for the rectangular table at the posh restaurant where you get to speak to only three people all evening and pay £60 a head for the privilege. Inequalities of salary and/or changing social circumstance (like becoming divorced or a single parent) make many restaurants too expensive a luxury now. The solution is to invite your friends to Sunday lunch on the Sunday nearest to the birthday, where everyone can chat in the kitchen/garden for two hours before sharing a rib of beef with organic vegetables, summer pudding and cheese. With a case of rioja, the whole thing will cost you £120 - spookily the same as the bill for two of you in a restaurant.

How do you discourage over-attentive waiters from placing your napkin over your lap?

Tell the waiter you don't want it there. Say you'd prefer to have it tucked into your shirt collar/ spread over your waistcoat/ knotted at the corners and placed on your head. Keep rejecting all his efforts until he tells you, "The hell with it, pal. Do it yourself" (ta-da!!).

What do you do when the famous celebrity chef appears at your table, insisting you try a new amuse-bouche, and proceeds to insert a spoonful of chive mash with chilli jam into your date's mouth?

I don't now when this unpleasant trend started, but it must be stopped. Try saying, "I'm afraid Catriona is allergic to starch/chilli/fruit. Please call an ambulance immediately."

Shopping

What do you do when you enter a clothes shop but instantly realise there's nothing in it you'd ever want to buy?

It's bad manners to turn round and leave after only clocking the merchandise. It's the equivalent of puking on the carpet. Propriety dictates that you must go to the left-hand side of the shop, finger between three and five garments in a thoughtful but ultimately regretful dumbshow, before leaving with a loud, matey "Thank you". No more than five garments, of course, because then they're required by law to come up and say, "D'you need any help?"

You are at the checkout in Tesco with a crammed trolley of groceries. A spotty youth appears, offering to help you pack. Do you assent?

Do you hell. The youth will undoubtedly pack the apricots and onions in the same bag, put the kilogram of washing powder down on top of the eggs and crush your yoghurts with the 12-pack of tonic water. But you must not hurt his feelings. You must insist on doing the packing yourself, while asking the hapless youth to unload the trolley for you.

A friend congratulates you on your stylish military-style jacket. You know that it comes from Primark, the low-price chainstore. Do you admit it, or pretend it came from Dolce & Gabbana?

You might as well admit it. The Primark label has now ceased to be the official flag of the Chav Republic, and has become the mark of the canny shopper. Just don't let everyone think it's where you buy all your clothes, that's all.

Travelling

Is it bad form to strike up a conversation on the Underground?

It depends whether your motives appear to be innocent or predatory. Remember the Tube is a long, airless, rattling, claustrophobic tin can, in which merely co-existing side by side with sweaty, pustular fellow humans is an ordeal. Tube journeys are conducted in a shared, mutually agreed silence. Any attempt to interest the opposite sex in your hectic schedule, the unseasonal heat or the exciting news in this evening's edition of the Evening Standard will be greeted with glances of contempt and ridicule. There is a reason why the young woman hanging from a strap has white wires trailing from her ears; it's because she doesn't want you to talk to her.

What else should one not do on a Tube train?

Eat white rice cakes. Pick your nose. Scrub your teeth (or anybody else's) with dental floss. Read The Da Vinci Code or its offshoots. Sit with one's legs a yard apart. Wear a Karrimor rucksack with dangling ocker billy-can. Play "You're Beautiful" on a bashed-up Yamaha, with a little pouch for the money dangling off the machine-heads. Say, "Of course Zidane was quite past it anyway..."

On The Phone

Under what circumstances do you answer your ringing mobile phone?

1) While walking, provided you're by yourself and at least 10 metres from any passer-by.

2) At an informal lunch with business colleagues who are boring you to death.

3) When shipwrecked (it might be a lifeboat).

Otherwise, it is dead naff to be summoned, like a servant, by a ringing noise.

Under what circumstances do you absolutely not ever answer a ringing mobile phone?

1) While proposing marriage in the Savoy Grill.

2) When speaking at a memorial service in St Martin-in-the-Fields.

3) While negotiating a loan over £250,000.

4) While interviewing Madonna/ President Bush/ the Queen/ Pope Benedict XVI.

5) While enjoying an intimate moment with anyone over the age of 35.

You're at work, you're busy, and a chatterbox friend rings up. How do you get him off the phone?

You say, "Gerry, I'd love to chat but I've got to go. There's a dozen people standing round my desk, listening to our conversation." It always works. No matter how unlikely it may seem, your chatty pal will instantly conjure up a "conference call" scenario and imagine a crowd of strangers grinning at his gauche phone manner

Your new partner's ex-wife or ex-husband keeps ringing up, demanding to speak to him/her. She treats you like a machine. What should you do?

Pretend to be a machine. Simply repeat the words, "Your call is important to us; please continue to hold" in a bored monotone, while waiting for your partner to realise who is "holding".

Children

Your son's new best friend, Torquil, has appalling nits. Normally you'd ban any kid thus afflicted from coming within 100 yards of your offspring - but his father is big in TV drama. What do you do?

Ask yourself which is more important: your son's health, or your selfish career as a media tart. The answer should then be simple. You must get Torquil (and his dad) to come round to the house more often. As for the nits, just persuade your son to shave his head as a precautionary measure. Tell him he'll be the dead spit of Vin Diesel.

You have acquired a trampoline, upon which all your child's friends bounce in an undisciplined rabble. How do you stop them having an accident?

You can't, unless you limit the number of bouncers to no more than three at a time. But even then, if a child comes flying off and breaks its neck, its parents could sue your sorry ass for a fortune. You must pin a notice to a tree in the garden, reading "All Children Use This Trampoline at Their Own Risk - The Management", after which you can retire to the kitchen and relax with a glass of sauvignon and a clear conscience.

Love & Sex

What behaviour is appropriate when exiting from a one-night stand?

However afflicted you may be with remorse, embarrassment or simple horror, on being confronted by the presence of last night's inamorata on the pillow beside you at dawn, it is only common politeness (for either gender) to make a weary sexual overture around 7am, offer a rudimentary breakfast around 8am, and tactfully hasten their departure around 8.30am with talk of a vital meeting, doctor's appointment (try not to sound as if it's a communicable disease) or early-rising cleaner. If you're at their place, it's unseemly to clamber into your clothing and vamoose before 7.30am, without indulging in pillow-talk and asking if there's any orange juice. Fran Lebowitz, when asked what she did with lovers who stayed the night, replied: "One hopes they have to leave early in the morning to go to school."

How do you behave if you're straight and a gay person asks you out?

Do not become all flustered, as if your virtue were under threat or your manhood/femininity impugned. Breathe normally. Loosen some clothing. Remember that it's flattering if someone finds you attractive enough to spend an evening with. But since a date implies that you may later be required to remove your clothing and adopt various horizontal postures, it is as well to decline from the start, with the diplomatic words, "I think my wife/husband might get a bit upset."

In dogging circles, what basic rules should be followed by the amateur?

When arriving at the pre-arranged dogging site, be discreet, ie no honking of horns or flashing of lights. Do not park too close to cars where Activity is taking place.

You are allowed to watch Activity through car windows, but should keep applause, whistles, smart remarks etc to a minimum. Helpful comments about comfort and posture-adjustment (eg "There's a metal flange under the passenger seat") are allowable. If invited to join in by Activity participants, ensure that people who got there before you have been given the opportunity to take part. Queue-jumping is frowned on.

What is the polite way to conclude an exchange of witty, flirtatious e-mail banter?

By going out for lunch with the banterer and suggesting you have sex as soon as possible. Like, duh.

Meeting People

When is it considered correct to kiss new acquaintances?

All the social-greeting malarkey has been through a lot of changes in the last couple of years. First, the Ab Fab air-kiss routine beloved of middle-class ladies has gone right out (too theatrical and false.) Second, among the younger elements the handshake has become as redundant as putting "Dear George" in an e-mail. With new acquaintances, you say "Hello" when you meet, and kiss them (for the first time) when you part.

NB Kissing friends on both cheeks is all fine and dandy, but the lady who has no time for such niceties and kisses all her male friends squarely on the lips whenever they meet will always be inexplicably popular.

How should one phrase a compliment to a friend who has recently, and obviously, had plastic surgery?

Under no circumstances say, "Holy mackerel, how much did you pay for those?" Subtlety is the key. Rather than make personal remarks about chins, noses, eyes or other body parts, stick to generalisations along the lines of, "You seem to be getting younger all the time; whatever is your secret?" and compliments to the partner: "Whatever Gervase is doing to you, you must make him go on doing it..."

What is the correct form of words when meeting an actor friend backstage and congratulating him on his performance, even though it was atrocious?

"Geoffrey! For God's sake! Were you on that stage or what??"

What do you do when, in the middle of a party, you completely forget the name of the friend whom you're trying to introduce to a stranger?

Switch straight into gush mode and say, "Darling, this is Cheryl, who has just moved next door. Cheryl, this is... My Best Friend, who has been my rock for at least 10 years. Oh, was that the doorbell?" With luck, your pal will be too disconcerted by this elevation of your relationship to notice that you can't remember who she is.

The Office

Now that such concepts as "dress down Friday" are popular in work environments, how casual can you afford to be in the office?

Gentlemen should show as little flesh as possible, taking especial care to hide naked stomachs, hairy backs, or tattooed arms. Ladies should go easy on the plunging neckline, the bare midriff and the waist-level lacy thong. Tight denim garments that draw attention to the crotch are also verboten. In other words: no lats, no tats, no tits, no bits, no knicks, no dicks.

Does one say hello to one's work colleagues every day, or behave as if you all exist in a time continuum?

Time-and-motion studies suggest that precious moments are squandered by informal exchanges each morning, eg "How was dinner with Michael?" "What on earth is happening on Lost, I can't make head nor tail of it." For maximum effectiveness, the office work agenda should forge ahead as if the comings and goings of staff were momentary interruptions. But sod that for a game of soldiers. In order to humanise your place of work, there should be maximum salutations every morning, including handshakes, offers of coffee, enquiries about the family and cries of appreciation of one's choice of shirt.

When is one obliged to get the teas in?

Once there were tea ladies, and the 4pm trolley bearing huge steaming samovars of PG Tips, and you knew where you were. Now the tea-run is left to chance, or the whim of whoever is feeling generous. Some upper-management types think it's beneath their dignity to get a tray of hot beverages for junior co-workers. The secret of limiting your tea-runs is to do it once a month but make a big production number of it: brewing the tea, removing the bags, offering buns, anchovy toast, scones, fondant fancies, Victoria sponge, three-tier cake stand and silver forks. People will make a mental note that you are Unusually Generous at Teatime and entertain positive feelings about you.

What should one do when one stumbles on two members of staff embracing in a private office?

You should not feel bad for intruding upon a private moment. The office is no place for private moments. It is a place for public transactions. You should feel no compunction in saying, "Get a room," and closing the door. Although, under the circumstances, "Get a broom cupboard," might be more appropriate.