Want to be a West End star? You have to get used to being out of work...

As this year's BBC talent show Over The Rainbow reaches the end of its yellow brick road, one talented hopeful will be thrust into West End stardom. Whoever is chosen will have it made. A role in a West End show sets you up for life, right?

Not necessarily, says Claire Greenway: "This business is a roller coaster. Very few people's careers are a steady climb. One minute I was making monkey noises in a tent at the O2, the next I had a leading role in a West End show."

Greenway, 29, from Merseyside, has been playing Sister Mary Patrick in Sister Act at the London Palladium for the past year. When she got the role, she was working as a pit singer in Damon Albarn's musical Monkey – Journey To The West.

Greenway says: "There's no 'working your way through' the ensemble, then on to a cover, then on to a small part, then a lead, then a star... It just doesn't work like that. You're just right for something, or you're not."

She had always wanted to be a performer. "My lightning-bolt moment was watching the tour of Les Miserables when I was nine," she says. "My mother swears I didn't breathe for the whole first act. I was totally in love."

Greenway trained at Chetham's School of Music and in musical theatre at the Royal Academy of Music, scoring her first role in Hot Mikado at Upstairs at the Gatehouse. "At the time, I didn't have an agent, which makes everything a little harder," she says. "For the audition, not only did I have to sing, dance and act, but I also had to play all the instruments I play. This meant dragging my sax out of the dust in the corner and panicking for a week."

Though she appears to have made it now, in her short career Greenway has played a Dr Martens-wearing fairy godmother, and has sung on film soundtracks and as a pit singer as well as holding down other jobs in telesales, jewellery sales and teaching.

Being a star can be hard graft, she says. "One day a week to cram in seeing friends and family, particularly if they have day jobs, is tough. Our Sundays go far too quickly, but the joy of a great part in a great show with a great cast is a gift."

As well as being a great all-rounder and having star quality, to make it in the West End, says Greenway, you need to get good at being out of work. "Make sure your well-being isn't associated with how well the next audition goes, and work out how to live your life inbetween jobs, because the times out of work can be longer than the times in..."

As a performer you are usually self-employed. You'll be contracted for anything from a few weeks to a year or more. Rights are tied into the contract, the overall ones agreed by Equity, and the ones specific to the show agreed with management and agents. Each show has Equity representatives – members of the cast who liaise with the union. In new shows there can be additional work around recording albums,filming promotional videos and adverts and making TV appearances.

Tim Driesen, 31, has just finished playing the role of Phoebus in Notre Dame de Paris in Antwerp, and has written a musical comedy Super Alice Smith. He says: "I think I have always known that I wanted to be a performer. It's a cliché, but as a child I put on shows in our back garden, where I charged admission in the shape of sweets."

Driesen trained in musical theatre at Laine Theatre Arts in Epsom. On graduating, he found an agent and won a role in Thank You For The Music, in which he played Donny Osmond and David Cassidy. "The audition was on a Friday and I started rehearsals on Monday. So I can't say my first job was the pay-off of a long, strung-out audition process."

But Driesen says: "To be able to sing, act and dance and be able to maintain the same standard of performance eight times a week, with clean-up rehearsals thrown in, is an intense process."

The economic downturn has hit the theatre hard. "There aren't many new shows being produced, and a lot more people stay in the same jobs for longer," he says. "You're only as good as your last job, and in recent years you're competing with celebrities, who will get in an audience but might not always be the best person for the part."

But the surge of good fringe productions, with casts of West End performers sharing the profits, means the quality of fringe shows has improved. "The best thing about working in the West End is you're working in one of the two capitals of theatre, says Driesen. "People come to watch you for special occasions, and you even get the occasional on-stage interval wedding proposal."

Get the spotlight on you

Most West End performers have done some kind of formal training. Visit ukperformingarts.co.uk for a list of courses and institutions.

Broadwayworld.com has a regular slot called The Audition Panel in which West End stars offer tales of their own auditions.

The Stage (thestage.co.uk) is the place to go for details of forthcoming auditions.