Before the peal of a nuptial church bell, the throwing of a bouquet or the tossing of a single confetto (is that really the singular of confetti?), you can smell wedding fever in the late spring air. If harnessed correctly the combined nervous energy of brides, their fathers, their grooms and best men and women could create an alternative energy source that would mean the end of fossil fuels. And the chief reason for this mass twitchiness is their speeches.

Having written many speeches and delivered even more, I feel a seasonal duty to try to ease the collective buttock-clenching and provide some helpful hints to all those upon whose wit and eloquence the state of the union now depends. So, my lords, ladies and gentlemen, I give you - the speeches.

The father of the bride (FOB)'s speech

His role: The FOB proposes the toast of health and happiness to the bride and bridegroom. That toast comes at the end of his speech and he will normally begin by welcoming the groom's family, relatives and the guests. It is traditional to welcome the groom into his family, then to say some warm and witty words about his daughter, and a few about his new son-in-law.

My advice: FOBs, proceed with care. This is the first speech and sets the tone for the reception. I once went to a wedding in Yorkshire where the FOB stood up and said bluntly: “I'm not going to say anything. They both know why,” and sat down. The occasion never did quite recover.

Tone is everything. Warm and heartfelt will offend nobody and win over everyone. If her choice wouldn't have been yours, fake it! It's her day. If you can, use it to say what you really feel. If you can't, say what you ought to be feeling. She'll treasure it always. But be wary: too much schmaltz can unbalance things the other way. I heard one FOB recite his daughter's every achievement, from a gold certificate at nursery for something with egg boxes, to her university degree. He looked crestfallen when the audience failed to respond to his proud, misty-eyed narration of how she had passed her driving test at the third attempt.

My advice is to gauge what most warm, right-thinking people would regard as justifiable pride and love. If there is any excess sentiment, save it for similar words about the bride's mother, the groom and your new in-laws. Remember, FOB can also stand for Fatuous Old Bloke.

The bridegroom (BG)'s speech

His role: The BG replies on behalf of himself and his bride. Traditionally he will thank the bride's parents for making the wedding, his parents for making him, and the guests for their generous gifts. If anyone couldn't attend because they are unwell, the groom should wish them a speedy recovery.

My advice: Hitting the rights notes is again crucial. Humour is great, but be careful. A groom I know began by saying that he had actually wanted a small wedding, just himself, his bride, his parents, her parents and the obstetrician! Her deeply religious family didn't get it. What's funny to you may not be to others. Try out any gag that is at all high-risk on various people beforehand.

Self-deprecating humour invariably goes down well. A somewhat unkempt friend of mine who lived with his parents began his speech with the words “Mum, Dad, you're gaining a daughter and losing a pig”. A bit stark, perhaps, and indeed they had a chance to reacquaint themselves with the pig shortly after the divorce.

However funny the BG is about himself, he should take the chance to say something heartfelt about his bride. Guests want to hear an expression of the BG's love. Some really do come just for the crying. And don't forget that light and shade in a speech makes it so much more enjoyable to digest. A gearshift from wit to sentiment is easy to achieve and very effective.

The BG will end by proposing the toast to the bridesmaids. Praise them, thank them for the wonderful job they have done - they have relatives in the room and you'll be ending on a warm note.

So be witty, be heartfelt, and err on the side of brevity. Five to seven minutes may not sound like a long time, but I've heard few bridegroom speeches that sustain much beyond that. Like any good speaker, leave your audience wanting more.

Almost everyone who gets up to speak at a wedding, in court or at a conference is nervous. A few tried and trusted techniques, applicable to any public speaker, will help. First, use your body fully. Stand tall, open your lungs. Hunched shoulders and a caved-in chest will damage voice production and reduce presence.

Secondly, try not to depend on a script. Become familiar enough with your speech to reduce it to a few cards at which you can glance from time to time. But if you do have to read it, don't worry. Practise so that you can read confidently, using pauses and modulating your speech to add texture and impact. Another tip is to listen to your speech on tape. You will have a strange “out-of-body” experience at first. But the more you practise, the more you will feel comfortable listening to yourself.

The key to any public speaking is the level of expectation you have of yourself. If you even half-expect to sound halting or timid, you will. Get yourself into a psychological place where you have heard yourself sounding confident and funny and, with practice, that's how you'll be.

When you're happy with the tape, try your speech on an audience of friends. That will hone your performance so you know when to slow down, speed up or pause for effect. Finally, watch yourself in a mirror or on video giving the speech. This will help to eliminate any distracting mannerisms and movements. Hands in front of your mouth, toying with a fringe or swaying about can all detract from your delivery.

The bride's speech

Her role: Despite the honourable tradition of involving women in the wedding day, notably in the role of bride, weddings have tended to be all-male affairs when it comes to the speeches. Not any more. Many brides will want to make a speech on their special day.

My advice: With no official toast to make, a bride has pretty free rein and is playing to a home audience. The day is quintessentially hers and, frankly, anything from her lips will go down well. It goes without saying that jokes are likely to hit the mark. A female friend of mine opened with: “Why was it so hard for me to find a man who is sensitive, caring and good-looking? Because most of those men already had boyfriends”. It brought the house down. (NB: this joke won't work at a civil partnership ceremony.)

The best man (BM)'s speech

His role: The BM's speech is traditionally the high point of the wedding reception. Officially he responds to the toast to the bridesmaids, but his real role is to entertain.

My advice: You may not be a professional speaker, but this audience is on your side and they like a bit of vulnerability. So why not make a virtue of your nerves? A decent joke at your own expense will break the ice and get everyone on your side.

Perhaps: “Standing here today, I feel a real sense of panic - and the definition of the word panic is when your wife, your girlfriend and your mortgage are all 30 days late at the same time (pause for laugh). That's not, of course, true of Tim (the groom), whose mortgage is fully paid up...” And yes, that is one that you should try out beforehand.

In any BM's speech there are safe, middling and dangerous subject areas. Safe ones include how the couple met, their great individual qualities, how they compliment each other and make a wonderful pair. Middling covers anecdotes about the groom as a child, adolescent and man. With taste-antennae activated, these can be fine and fun. Without, they can be upsetting, affect relationships and cause lasting resentment. Dangerous includes the bride and groom's former love life, his personal habits and the stag night.

A BM I once heard thought it hugely funny to go through the groom's little black book of conquests, giving each one a rating. He then revealed that the groom had kept a pair of each of their knickers under his bed. When he met his bride he became embarrassed that the Tom Jones effect might not work for her, and buried the entire knicker collection in his garden. For the guests it was definitely not a case of “thank you for sharing”. Curious as it may seem to the “No, they'll love this one, honest” breed of BM, revealing your best mate to his new wife and family as a serial shagger and fetishist is really not endearing.

In addition to poor taste, the BM has several enemies. First and foremost, drink. It doesn't make you funnier, it makes you embarrassing, incoherent and insensitive to the reaction you are getting. The very drunk best man who opened with, “Don't they look like a new house? Her freshly painted, him plastered” was in fact so far gone himself that he took the total lack of audience reaction as a green light to hit them with his treasure trove of condom and vibrator material. Guests want a best man to succeed. They are not so particular about a drunk best man succeeding. Anything more than one drink before your speech is dangerous. It is worth noting that you may be interrupted by quips and comments from family and guests. A good rule is to be at least as sober - and therefore mentally agile - as these good-natured hecklers. You will be unable to respond wittily if your synapses are raddled with Drambuie.

Judge your audience: Try to find out as much as you can about them in advance. In particular, be aware of cultural and religious issues, and check for any particular sensibilities. This will enable you to avoid unwitting elephant-traps such as jokes about memory loss if a beloved relative has Alzheimer's.

When speaking, stay fluid. If something really isn't working, try to be flexible enough mentally to cut and paste it into another section of the speech. Blunder into a verbal cul de sac and you will feel the energy in the room disappear. It's easy to ride a wave of positive energy - and almost impossible to create one if you have lost an audience.

Insults: Forgive me for stating the obvious, but insults are insults - so don't. A bit of good-natured mickey-taking is fine, but crossing the line into areas capable of causing real offence is easily done and should be avoided at all costs. Comments touching on such subjects as weight, height, academic achievement and sporting prowess should be weighed, measured and put out to consultation before use.

Jokes: The best humour in a wedding speech will always have a personal resonance. There is no substitute for good, unslurred, clean or even slightly risqué jokes and stories involving key members of the wedding party. They are simply the best way to warm up the room. Ask around widely for family stories or material that you can turn into jokes and anecdotes. Cheat! Some great stories can be personalised around the lives of the key people in question. No one minds if the story is apocryphal, as long as it is witty and appears to fit the personality of the person about whom it is told.

Sometimes, however, a BM will not be able to locate or construct such funny stories and will feel the need to tell stand-alone jokes. Nothing wrong with that if they are well judged and funny. A best man I heard recently got a great reaction to the jokes “Why do men want to marry virgins? Because they can't handle criticism”, and “Why do men find it difficult to establish eye contact? Breasts don't have eyes”.

If you are being likeable and self-deprecating about men, even jokes with the words “virgin” and “breasts” are acceptable. Pull that off, and for BM read Blooming Marvellous.

So, can I ask you to be upstanding and to charge your glasses. The toast is “the father of the bride, the groom, the bride and the best man”. May they be infused with taste, timing, tone, wit, preparation, warmth, abstinence and confidence. And if all that fails, just cut to the song.

The author is a barrister, after-dinner speaker and comedy writer. See his website at clivecoleman.co.uk

For Times writers' suggestions on choosing the right wedding music, go to timesonline.co.uk/music

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