Style: Waiter, waiter there's a fly in my suit ...

John Walsh feels cool, dashing and funky in a lime-green Ozwald Boateng number - but all he attracts is greenfly

"The choice you're looking at," the man said, "is between your cerise, your orange, your pale lime and your dark purple check." Well of course. If you're going to splash out on an Ozwald Boateng suit, it has to be one of his poster-paint-coloured numbers. He does perfectly respectable charcoal grey business suits with a discreetly coloured pinstripe, but that's not the point. The point is peacockery, flamboyance and showing off - presenting yourself, just for one evening, in a two-piece neck-to- ankle flag of vainglory.

The fashion desk assured me that cerise was the only colour to be seen in this season, darling, but it just didn't suit me. Since I'm six foot two, I'm supposed to be able to carry off the most ridiculous colours, but clad in Boateng cerise (which is, strictly speaking, more mauve than cherry in hue) I looked like someone recently ejected, on grounds of taste, from a pyjama party in Lewisham.

Crestfallen, I tried on the orange version, which had an interesting pale pink vertical stripe and a lovely soft apricot glow to the material (all the coloured suits are made from the same hybrid of worsted, mohair and polyester and are stunningly light and summery; you couldn't wear them a minute before May or a second after September). But no dice. I know there are Ozwald clients out there who'd look cool and manly in orange (Mick Hucknall? Chris Evans?), but on me the magic wasn't working. Now I resembled a minor African potentate on his way to a tribal wedding.

The pale lime, though ... it was an unusually gorgeous greengage thing, actually, with a nifty blue thread peeping through, as a sort of descant. Mr Boateng prides himself on what he calls "bespoke couture", as if each suit, in each size, colour and style, had been made specially for each customer. It's a nonsensical conceit, of course - but that doesn't explain why the size 44 should have fitted me so perfectly. The jacket beefed out one's shoulders, it flattened one's (alarmingly capacious these days) stomach, it came in at the waist just so without making you look like Mr Pearl the corsetaire, it flared out just a fraction at the skirt. The jacket flaps are cut square, not rounded, so that when it's buttoned the southern rim is a completely straight line. It's fantastically elegant. The trousers are cut slender with Stanley-knife crease, the legs are so light; they don't break on your shoe as smoothly as you might like, but you can live with that.

As you sway this way and that in front of the mirror, marvelling at the rippling back muscles you've suddenly acquired, the staff accessorize you with a bright blue cotton-polyester shirt (to tone with the jacket's blue Day-Glo lining) and a blue-green tie with an archery target bang in the middle. The suit is pounds 895, the shirt pounds 95 (and worth every penny) and the tie pounds 60.

Thus encased in eleven hundred quid's worth of schmutter, I walked off to the launch of Amanda Foreman's lovely biography of the 18th century queen of fashion, Georgiana, Duchess of Devonshire, at the Orangery, in Holland Park. In Notting Hill, at least a dozen unaccompanied women walked past me (was there a singles convention on?), and I swear every one did that beady-eyed sidelong appraisal women do, the one that means not "Christ, what a hunk" but "Good God, where did that lout get his hands on such handsome clothes?".

In trendy restaurant the Pharmacy, the waitress said "I love your suit. Where'd you get it?" and brushed a lurking greenfly off the collar. I was accompanied by two women, who both said "Look at you" in that non- committal way, although both frankly admired the Day-Glo lining. Typical. At the party, Isobel Wolf said: "You look like a modern-day Auberon." You mean Waugh? Well thanks a bunch ... "No, Oberon. In Midsummer Night's Dream." Oh right. The King of the Fairies.

One or two chaps ignored the suit but, looking at the tie, fired an imaginary arrow into my chest. Uproarious. More insects settled on the lapels like tiny squatters. Emma Tennant surveyed my colour scheme with her head on one side and said: "Mmm. Blue and green/Should never be seen/Except upon an Irish Queen."

Some kind of theme was beginning to emerge. I didn't care. The right suit makes you feel light in spirit, cool, dashing and funky, as if at any moment you might break into a tap dance. That was how I felt in Mr Boateng's little green number. The only drawback were the greenfly who, by the time I left, had clustered round me like barnacles on the QE2. It's bound to be disappointing, isn't it, when you wear the coolest suit in central London and can only attract a flying (if colour-co-ordinated) aphid.

Ozwald Boateng, 9 Vigo Street, London W1 (0171-734 6868). Ready-to-wear suits cost pounds 895, bespoke suits pounds 2,000 on average; shirts from pounds 95 to pounds 295; ties pounds 60.