For any man facing up to the challenge of representing his closest friend on the biggest day of his life, watching the opening scene of the recent hit British comedy I Give it a Year should be at the top of any pre-wedding check list. In it, the hapless buffoon played by Mr Stephen Merchant delivers possibly the most toe-curling best man's speech it's possible to imagine. It's so bad that by the end not even the groom can disguise his horror. Whatever people say about this being the most supportive audience you'll ever face, the best man's speech is a tightrope. You will either traverse it successfully and be hailed as the hero who lights the fuse for the fun part of the evening, or you'll fall horribly and want to spend the rest of the wedding hiding in a cubicle in the portable toilets. I have witnessed a man who boasted about being a much in-demand after-dinner speaker flatten the atmosphere in a previously ebullient marquee, so do yourself - and the groom - a favour, and take heed of the advice on the slides, above.
Humiliating the groom
As best man your job is to support your friend throughout an exciting but stressful day. Neither he, nor anybody else, wants to hear about the appalling, tawdry things that went down on that "legendary" university rugby tour.
Speaking in riddles
If it's bad to recount unflattering anecdotes it's almost worse to allude to juvenile misadventures without revealing what they are. Try to entertain the whole party, not just the guys who were on the stag night.
Talking for too long
Keep it short and sweet - five minutes is perfect. People want to hear what you have to say, but go on too long and their thoughts will turn to dinner, or their wish for another drink. It's best to leave them wanting more.