For the last seven months, since Mark's irresistible invitation to be best man at his wedding, I've been inundated with advice on public speaking, reminders about my limitless duties, never-known-to-fail jokes and spoof telegrams - all with the reassuring counsel (Mark is a doctor) that it will certainly be the most stressful day of my life.
The weekend mood of fellow travellers on the Underground heightens my growing nervousness. At the clothes hire shop I am reacquainted with the morning suit I tried on several months ago, before that holiday in Portugal and the annual summer gut. By now I'm so distracted thinking up elusive punch lines that I leave my credit card behind.
Could I improve that gag? Do I toast the bridesmaids?
As I plunge into a cab, I accidentally let my top hat tumble on to the pavement. 'Best man, sir?', the driver asks with a knowing look, recognising the signs of distress.
Back home, I pass the nervous minutes with an uncharacteristic bout of flat cleaning. Mark arrives, looking disconcertingly relaxed and the evening passes with undue haste: a quick hamburger and surprisingly little alcohol are followed by a full dress rehearsal of my speech. We go to bed early, having taken several sleeping
Saturday: I wake up in the middle of a dream about Frank Sinatra. My mind dwells obsessively on public speaking, on talking humourlessly to a sullenly unresponsive audience, and on the speech's core - a Frank Sinatra joke - dying quietly on its feet.
As I write the speech out on index cards, the heavy-handed humour becomes more apparent with each redraft. No need for the audience to wonder what I do for a living. They will immediately think I must be an accountant.
In the cold light of day the hired morning suit looks even more ludicrous. The car journey from London down to Epsom in Surrey is spent in silent contemplation of our respective fates.
Two swift pints at the pub beforehand help the church service pass in a whirl, though all the hymns sound like My Way. Outside the church there is a lengthy photocall, and for several blissful minutes I'm too busy to visualise my impending stage debut. My first slip as best man comes during the rush to the reception, when I forget to check that everybody has a lift.
On arrival, I walk to the top table for my first view of the firing squad. Friends have begun to express concern at my condition: in response my furrowed brow deepens and my palms gush sweat. A sumptuous meal is served, but my appetite has gone.
Instead, I re-read my index cards, while a devil inside torments me. This simply is not funny, he says, you cannot be serious about using this joke?
Out of the blue a microphone appears (A microphone? Nobody mentioned a microphone]) and the speeches begin, to what seems like tumultuous applause. Despite my condition, I recognise that Mark's speech has finished and . . . am astonished by my sudden calm. The room is now generating such a welcoming hush that I stop sweating and start exuding sang-froid.
I read the cards (this is so easy) and my carefully crafted droll asides are met with unjustified hilarity. Just as I feel I'm really getting into my stride my 10 minutes are up and I reluctantly sit down, trying hard to look modest and relaxed. Perhaps I could do this professionally?
The Sinatra joke? It bombed - but who cares?
Sunday: I wake up dreaming of Frank Sinatra.
The author is indeed an accountant, and was best man at the wedding of Christine Wells and Mark Free on 12 September 1992.