You've seen the ads. You've spoken to the careers officer. You are16 and you are already using Estee Lauder Advanced Night Repair Fluid (good boy). You are simply gagging to sign on the dotted line. But before embarking on this lifetime commitment, take a break, have a KitKat, and ask yourself the $6m question: do you have what it takes to be gay?

It's not like being heterosexual, you know. Heterosexuals jump out of bed in the mornings and they're, like, straight, and no one cares if you haven't polished your nipple rings for a week (I ran out of Mr Muscle - sue me). The world, what's left of it, is created in heterosexuals' image - that's why the colour scheme is black and white - so their sense of self (importance) is constantly, quietly, tediously, upheld, reinforced and massaged.

The straight world is an ordered, signposted environment sociologists would call "stable" and what the truly enlightened would call "static", but the fact remains that heterosexuals don't have to construct themselves every 24 hours, invent their lifestyle and culture as they go along, decide on who they're going to be, dance to Kylie remixes, sleep with strangers (perfect strangers, fortunately) and know the five best places in London to have emergency liposuction. Sad but true: many heterosexuals have never even been to a decent Cantonese restaurant, let alone to the ballet (quick - a queen at the back just fainted). This is nothing to be proud of, but ignorance can be bliss. Imagine being "normal" and being able to go home in the evenings, watch Emmerdale (and like it), have a Menu Master meal, be in bed by half-past ten, and not be tortured by a nagging feeling that there's a party somewhere with your name on it, and, ooh, you aren't there, Miss Thing.

No - I can't imagine it either.

My point: if you choose to accept this mission, you should know that being gay takes commitment. We're not talking (yawn) biological destiny, we're talking decisions, decisions, decisions, not to mention a packed diary. Monday, the Beauty Shoppe: should you shave, pluck or wax away your body hair? Tuesday, the hairdresser: is it wax, gel, putty or shaper for the hair atop your body (keep it cropped). Mon-Fri: can you make it to the gym every day? Or just - bare minimum - three times a week? You ought to try for every day: not only does exercise make you feel good in a society that often seems dedicated to making you feel bad, you'll need the muscle to fend off queer bashers, and it'll help to get your metabolism up, up, up so you can go clubbing almost every night.

You should get used to the nights, too, because gay men are nocturnal creatures. Yes, we have been spotted during the daylight hours, bumping our way through the daily grind, but as one gay disco anthem proclaims: "In the evening/the real me comes alive/it helps me to survive". We flock together, under the close, comforting cloak of darkness, redistributing energy, grouping, belonging, being. Perhaps that's why we identify so readily with vampires. That and the fabulous capes.

Ah, the clothes. Anything goes: after the high and daunting hurdle of accepting your own outlaw sexuality, what possible fears could tartan trousers, leather jockstraps and chiffon tops hold? None. Out of the closet, into the wardrobe.

It's back to reinvention - "If I am not that, what am I?" - and clothes can literally make (and remake) the man. Once free of society's straitjacket, it's only natural that you'll want to slip into something more comfortable. Or colourful. Or crotchless. Each outfit comes with an identity quite as disposable as your income (we'll get to that later): butch one moment, boyish the next, with the preppie look thrown in occasionally, just for shock value. Labels, labels, labels, darling. They exist solely to be played with, be they Westwood or Smith or Richards or boring old gender roles.

Post-coming out, everything is easier: even moisturiser. And skin toner. And eye cream. And body scrub. And snowflakes that play on your nose and eyelashes (show tunes! That's the other thing - you should know about show tunes). Vanity becomes not merely permissible, but necessary. It says I Am What I Am, I Am My Own Special Creation. The contradiction being, of course, that you are not your own special creation, but beginning to resemble every other urban gay man. You are quite literally taking in the subculture's visual codes through your pores, and you in turn transmit those codes to others, and they back to you, in an endless hall of mirrors - and mixed metaphors.

I hate to sound like the lady at the beginning of Fame, but if you want gayness, it's going to cost, though probably no more than any swinging single existence ... if you forget the pink pounds you'll be spending on the collected works of Joe Orton, the Judy Garland CDs, recreational drugs, Bette Davis videos and that monthly gallon of amyl nitrate.

You say that doesn't bother you? It's money well spent? Who else are you about to lavish it on? You're going to sign the contract? And, thanks, but you knew all this already?

Great. I have half an hour to spare out of my glamorous life and I waste it preaching to the perverted.