Last Sunday at the American Music Awards, the singer J-Lo slipped and fell on to her bottom. Spookily, three days earlier, I had also fallen over while performing.

There were, however, a couple of differences between the tumbles. J-Lo had been climbing a human staircase of nearly nude male dancers and was wearing hot pants and singing lustily. I, on the other hand, was decently clad and quietly getting out of my chair to give a speech at a formal dinner for investors in Japanese equities. I tripped over my handbag and landed spread-eagled on the floor, my chin hitting the carpet. Crash, bang, wallop. The microphone I was wearing ensured that anyone who did not see the fall heard it.

Like most people, I find public speaking more frightening than spiders or the prospect of being mugged in a dark alley. What is terrifying is the risk of humiliation, of metaphorically falling flat on one's face. It never occurred to me that I needed to fear it literally, too.

Unlike most phobias, being frightened of speaking in public is entirely rational. Most speeches go badly, even if one manages to stay upright throughout. It is not just after-dinner speaking, when the audience is either drunk, wanting to go home or wishing you were someone funnier. Even during the day, audiences are often busier playing Brick Breaker on their BlackBerrys, e-mailing, sleeping or talking among themselves.

While nearly all men are poor at public speaking, women are even worse. This is partly because women cannot tell jokes, but also because we are better at self-awareness and therefore know that our speech is average and the audience would rather be doing something else – thoughts that do little to enhance performance.

To combat fear and innate hopelessness, I try quite hard to be better. Every time a book about public speaking arrives on my desk, I skim it for tips. Mostly they tell you to “relax” and to “be yourself” – which is downright irresponsible. This works only for the one in a billion who is born a brilliant speaker. For everyone else, being good means reaching such an elevated level of nervousness and artifice that you can present an entirely convincing picture of authenticity and relaxation.

The most recent book, The Top 100, contains tips from the 100 best speakers of all time and tells us that Bill Clinton's secret weapon is to “inspire confidence” and Gandhi's was to “avoid ego”. This may be true but is not terribly helpful. It is like watching a video of Rudolf Nureyev being the black swan and then expecting to be able to twirl round the living room in a similar fashion yourself.

I have only come across two bits of helpful advice. The first is practise, practise, practise. This is a bore because it takes a lot of time, but there is no way round it. The second is to junk all aids. PowerPoint is a crutch. It is an ugly thing in itself and must be thrown away if you want to walk smoothly. Equally, you must never read a speech. Write it, learn it and then leave it at home, speaking with minimal notes.

I supplement these with two further tips of my own, neither of which requires effort. The first is to make sure that the person speaking before you is really boring and has a laptop full of overcomplicated, PowerPoint slides. The second is to pick the right audience. Once, I gave an after dinner speech to middle managers in HR from the north of England. I had done a great deal of rehearsing and failed to sleep the night before and taken beta-blockers and so was all set and keyed up to the perfect pitch. The fact that the speech was catastrophic (not one laugh) made me feel bad for several weeks afterwards. But I now see it was the audience's fault. They were never going to like a snotty Londoner being superior about management fads anyway.

You might be wondering how J-Lo and I recovered from our tumbles. She picked herself up and went on dancing. I was picked up by the event organisers and reunited with my shoe, which had come off. I then professed the fall to have been deliberate – I could think of no joke with which to start my speech so had gone for slapstick instead.

I think there was some polite laughter. Which there might not have been had I started with the only joke I can ever remember. What did the policeman say to his stomach? You're under a vest.