Comedian Paul Merton reminisced about his unlikely rise from working-class Morden schoolboy to celebrity stardom at a Wimbledon BookFest event to promote his autobiography.

Best-known for his appearances on the BBC's Have I Got News For You, the comedian recounted his journey from Morden Hall Road to a job at Tooting Employment Office and two years' of fish paste sandwiches in a Streatham bedsit while he climbed the comedy ladder.

The son of a tube driver, he spent much of his childhood at the end of the Northern line, attending St Teresa's RC Primary School and watching the latest Morecambe and Wise at the old Odeon opposite Morden Station.

Speaking to the Wimbledon Guardian after the event on Wimbledon Common on Saturday night, he said: "We moved to Morden from Fulham and I thought Morden was the countryside because there were fields with some cows in them and the dual carriageway had a grass strip down the middle.

"I moved from a council estate in Fulham so it felt like a fairly exciting place to move to - there was lots of space."

He wanted to be a comedian from the moment he saw a clown perform at the open-air theatre in Bishops Park, Fulham and would get on the tube to South Wimbledon to visit a shop that sold silent films in Kingston Road.

A shy child, he recalls one moment of comic inspiration, when walking around the back of Crown House in high winds, a hat blew out of a window, closely followed by a ginger wig and then a large man appeared chasing them.

He says the "Hat-Wig-Man race" which ensued was one of those moments of "magic", seen only by himself, which appealed to his surreal sense of humour.

Merton was part of the first comprehensive intake at Wimbledon College, which he says was a bit of a "culture shock" - both for himself and the school, who "didn't really know what to do with all these Mitcham and Morden boys with their shirt tails hanging out and bits of egg on their face."

Memories of schooling in Wimbledon tell a story of class struggle, where a careers advisor told him to aim for a career in shelf-filling. But he made an important friendship in the common room with John Irwin, who went on to co-write the 'Paul Merton' sketch show.

Asked how he overcame his timidity, he said: "Working in Tooting Employment Office you have to pick up the phone every day and talk to people.

"Forcing yourself - you realise nothing bad is going to happen. Growing up and just getting more used to talking people."

Merton's big moment was his stand-up debut at The Comedy Store in 1982 with a sketch about a policeman on the Streatham High Road.

Born 'Martin', he changed his name to 'Merton', after his home borough, when joining Equity, the performers trade union where there was already a 'Paul Martin'.

With a host of successful comedy series under his belt, he now prefers to live off Tottenham Court, conveniently close to the BBC headquarters.

He said: "If I lived anywhere other than central London, Wimbledon would be a good place to live because it is great - with all the space and the Common and the shops and pubs.

"Its a great place if you've got the money to live here."

Paul Merton's autobiography, Only When I Laugh, is out now.