How to give the performance of a lifetime at the Oscars

It was Marlon Brando who leant the latter to his cost when he boycotted the ceremony in 1972, American Indian rights activist Sacheen Littlefeather taking his place.

The move was clearly an act of political intent from an actor who already had a reputation for being, let's say, a little tempestuous, but when Littlefeather appeared apologetically on stage, it left the audience bemused rather than fired up to march on the Hollywood studios.

"It's not a time to make a political statement," says speech analyst Alan Stevens. "The problem is no-one is really listening. Everyone in the audience is wondering if they're going to win the next category or commiserating with the person next to them for having lost out; everyone at home is saying, 'Ooh look at that dress,' or 'Doesn't he look old'. No one is interested in hearing some actor or other on their soap box."

As is the way with actors, no one admits to having written an acceptance speech beforehand. They are, they say, just grateful to be nominated and besides, jotting down a few grateful words would only be tempting fate.

"It's complete nonsense," says Stevens. "Everyone writes a speech, the problem is they get side-tracked. These are actors, people who get paid handsomely for performing other people's lines, but come the awards season it's truly amazing how many of them go completely off message."

Steven's own award for all-time worst acceptance speech comes not from the Oscars, but the Golden Globes. Kate Winslet blubbed her way through a cringeworthy few minutes after being named Best Actress for Revolutionary Road in 2009, thanking everyone she could, but crucially forgetting the name of her fellow nominee. For one night only, Angelina Jolie was referred to simply as, "the other one".

"If Kate Winslet, usually a picture of understated charm can go to pieces, anyone can," says Stevens. "Of course you should thank people, but not everyone you have ever met and the tendency to gush is one of the most common afflictions to strike Oscar winners."

While Winslet managed to recover her composure when she picked up the same award at the Oscars a month or so later, the mere sight of those little golden statues are enough to turn even the most sane stars into rambling simpletons.

The 2001 awards were undoubtedly a landmark in the history of the Oscars and much needed recognition for America's black actors with Denzel Washington, Sidney Poitier and Halle Berry all winning awards. However, the significance of the evening was all but overshadowed by Berry's on-stage convulsions and is regularly cited as the Oscars' most embarrassing moment.

While the Monsters Ball actress had no shortage of words, Gwyneth Paltrow was barely able to talk when she won for Shakespeare in Love two years earlier. The tears started before she had left her seat and by the time she had thanked every member of her family, including a few who were deceased, the entire audience was trying not to look her way.

Equally uncomfortable are attempts at comedy, but for a lesson in how to deliver a light-hearted yet touching acceptance speech, Stevens says look no further than Colin Firth.

The actor is widely tipped to win this year's Best Actor Oscar for his portrayal of George VI in The King's Speech and if his warm-up at the Golden Globes was anything to go by his could be the best speech of the night.

"All too often someone hears the previous winner getting a laugh, rips up their own speech and tries to outdo them," says Stevens. "It never ever works. Colin Firth's speech at the Golden Globes was pretty near perfect. He thanked the rest of the cast, joked about a midlife crisis and how the award was the one thing between him and a Harley Davidson and got off before it all drifted into sentimentality.

For those Oscar nominees who haven't seen it, they would do well to take a quick look before next month's ceremony. It might just help them avoid a career- defining moment of complete embarrassment."

It wouldn't be the Oscars without tears, tantrums and tiaras, but they could also do with a few more Joe Pescis, who avoided any painfully awkward moments when he won Best Supporting Actor for Goodfellas in 1991.

"It was a privilege," he said. "Thank you."