Noel Fielding: rocking a new look

"People are so boring these days," says Noel Fielding as he hoists himself into his Eno bell-bottoms, slips on an orange wig and struts with a guitar. Fielding, surrealist comic, painter and dandy, is recreating the glam rock 1970s. Just watching his bonkers sitcom The Mighty Boosh, or seeing him coyly flirting with Russell Brand on The Big Fat Quiz Of The Year, you know this must be his era. Fielding is rarely seen without a splash of makeup, big heels and even bigger hair.

Actually, he says, it's his parents' era. They were in their late teens when he was born, adored Bowie and Bolan, wore tight tank tops and flares, and showed him the way sartorially. They were more like an older brother and sister when he was young. He'd come down in the morning for his cereal and have to climb over dozens of post-party bodies. No, he says, of course he didn't like it.

It made him inhibited and a little stiff. "I did a joke about that in my standup. Mum came to parents' evening in a really short skirt and massive leather boots, and I was so embarrassed. So in the joke my dad says, 'It's not your mum, it's Alice Cooper.' And it turns out he's left my mum for Alice Cooper. And Alice makes my packed lunches and stuff."

Today, Fielding is dressing up as David Bowie, Brian Eno and German performance artist Ulay as a tribute to a new glam rock exhibition at Tate Liverpool. "I make an all right Bowie," he says, then changes his mind. "Actually, I look more like Cilla Black with that wig. He's got that amazing body… he just ate raw eggs and took cocaine, didn't he? He's so thin, you don't know what he is – sort of male, sort of female. There's something about him that's a bit alien."

Is this the kind of stuff he wore at school? God, no, Fielding says. He was quiet, introverted, young for his age. So when did he morph into the outré extrovert ? He says he's not sure he ever did. "I think I'm still quiet. So is Julian [Barratt, co-writer and fellow star of The Mighty Boosh]. Apart from the Conchords, we're probably the two shyest comedians you'll ever meet."

As a young boy, he was often mistaken for a girl. He'd be happy enough if that happened now, but back then it upset him. "It's not what you want when you're 12 or 13 – people going, 'Hello, young lady. Oh, sorry, young man…' I grew up in south London with a lot of geezers. I had the piss taken out of me for being skinny."

The strange thing is, he says, when he tries to look feminine these days he just looks like a bloke in drag. "Look at me as Eno," he says. "My features are all wrong." He's got a point – all chin and big, broken nose. "Eno's got a tiny head, a small nose and big lips, and he looks quite like a woman. Whereas I've got a big face."

At 15 he became a goth for pragmatic reasons – he had a series of goth girlfriends. For the first time he dabbled in makeup. "There were three of them who dressed me up. I loved that. All you needed was a mirror, makeup, clothes and people."

He went on to do a national diploma at art college, followed by a degree and an MA in art. Even then, he says, he was unsure of himself. "A lot of people were quite cool and dapper and streetwise. I didn't really have anything going on. I was completely bamboozled by the fact that this beautiful girl fancied me."

Fielding has a reputation as a party animal, but for a long time, he says, this couldn't have been further from the truth. After university, he caught hepatitis, was ill and exhausted for a year, and couldn't drink alcohol for the next five.

So the whole image – the brash, wasted narcissist – is just a confection? Well, not quite, he says. In his late 20s, when The Mighty Boosh became successful, he did start drinking and drugging, hanging out with Amy Winehouse and the Libertines.

Fielding had seen Barratt perform at a gig, got chatting to him and told him he was into similar stuff. Barratt asked if he'd like to help him create a modern-day Goodies. "That was our frame of reference. If he'd said anything else, I'd probably have said no."

The Mighty Boosh is set in a zoo populated by talking animals, freaks and alien kidnappers. Fielding says it's more rock'n'roll comedy than straight comedy, and he has a point. The pair introduce "glam folk", a hybrid of glam rock and folk, with a Kiss-like band singing Scarborough Fair, and at one point a David Bowie character emerges from a magic forest to warn Vince Noir, Fielding's character, "not to get lured away again". One animation sequence features Eno (in the form of a Frisbee) fighting with Bryan Ferry (a kite). Fielding's favourite homage to glam rock is the alien travelling the Milky Way in a glitterball, using the last resources from each planet to party. "A bit like Tutankhamun with 10% Kate Moss in him."

While Barratt's character, Howard Moon, is intellectually self-satisfied, Fielding's Noir is simply vain, obsessed with his hair. Is he in real life? "Oh yes." When he teams up with Russell Brand for The Big Fat Quiz, they come across as a pair of preening cats. Who's more vain? "Him definitely. Hahahaha!" He pauses. "I think so," he adds less certainly.

Like Brand, Fielding can get carried away. When the art critic Waldemar Januszczak ridiculed the idea of Fielding interviewing Damien Hirst, Fielding responded by suggesting to his Twitter followers that they ought to give Januszczak something back in return. The art critic soon found himself attacked by Fielding fans on Twitter. "He said getting me to interview Damien Hirst was like getting Coco the Clown to read the news," Fielding says now. "But he'd not seen the programme, he didn't know I'd got an MA in art, that I've had two exhibitions, I've shown my stuff at Saatchi's. It's kind of insulting. And he and his friends were laughing about it on Twitter, which is a public space. They were saying, 'I heard he'd got an ND from Croydon!' I thought, what a fucking snob. I didn't say anything to him, I just said, 'Oh, this is what he's done; what do we think of that?'" He pauses. "You shouldn't do that if you've got 5,000 followers and the other person's got 400,000, because you're not going to win. I felt bad because he got slaughtered, but I'm sure he could take it."

Now he's posing as performance artist Ulay. Fielding looks surprisingly tough – handsome rather than pretty. "I loved being a man-woman," he says of the picture. "It's much more interesting than being one or the other." Does he regard himself as a cross-dresser? Well, he says, he likes a nice frock. "Yeah, I'd say yes probably. I do wear dresses sometimes." Is he attracted to men as well as to women? "The boy thing didn't really work for me," he says, sounding almost apologetic. "I can kiss boys, but beyond that it doesn't really do it for me. I was in a band with a boy who was quite androgynous and a bit bisexual, and we used to play up to that a little bit to be provocative, in a theatrical way, but I guess you either are or aren't."

It's depressing how conventional people are today, he says. "Everything's so conservative. Kids love Lady Gaga because she's a freak, and she's one of the few people doing that, but unfortunately Lady Gaga hasn't got the tunes. She's not David Bowie or Roxy Music." He's on a roll now. "She's quite bad. I like what she's doing, but there's no reason for it. You're in a massive bath with 20 dancers – what does it mean? What's it got to do with music, other than that she likes to be enigmatic and dress up?"

Everything has got a bit square nowadays, he says. "The X Factor sucks. Dreadful. When you look at One Direction, it's like they're in Topman."

Fielding is 40 this year, and is beginning to feel it. "The older you get, the more you have to tone it down. When you're young, you can wear what you want." He enjoyed replicating Bruce McLean's image Pose Work For Plinths, after all the cross-dressing. "He wore a black rollneck and black trousers. Apparently, the original was a piss-take of a Henry Moore sculpture."

So is it time for him to start wearing sensible shoes and black rollnecks? He looks appalled. No, he says, with the world in the state it is, we need the spirit of glam more than ever. "There's a massive fantasy element to glam rock: it's all about escapism." He's never been interested in settling down, embracing the mundane, and doesn't see why he should start now. "I've never had to stop and get a real job and do real things. I've always lived in a perpetual state of fantasy."