SCORES of A-listers, from models Elizabeth Hurley and Yasmin le Bon to domestic goddess Nigella Lawson and actress Natascha McElhone, wouldn't trust anyone else with their trademark tresses. Natalie Imbruglia is due an appointment any day now and Fearne Cotton was recently spotted with the stylist's products, having gone dramatically from blonde to brunette.
And though, as the First Lady of Colour, she commands a minimum of 400 for highlights – one woman even travels from Scotland every month rather than take her ahir elsewhere - Jo Hansford left school at 15 with no qualifications and even less idea about the world of hairdressing.
"I never intended to be a colourist," she says from her salon in Mayfair, pampered pooch Stella, a key member of the team, barking away in the background (she's been shut in another room to give her owner some peace but she's not very happy about it and is making her feelings known in no uncertain terms). "I'd never even been to a hairdresser because we had no money. I just wore my hair up in a ponytail."
In fact, the Londoner had set her heart on working as a make-up artist for television and had even won an apprenticeship at the BBC. But she needed to be 19, "and, as I left school at 15 because I hated it so much, I thought, 'What am I going to do for four years?'"
The BBC suggested she take up hairdressing, because she would need those skills for television as well, and the local careers office offered her a choice of two apprenticeships: one in Ealing, the other in Mayfair.
"I thought Mayfair sounded more interesting but I had no idea where it was," she laughs. "It was a massive salon next to Claridge's and my boss was this terrible old queen who made me cry every day. But he was a genius and he taught me so much. I hated the hairdressing – it was all backcombing and rollers in those days – but at one point I had to go into the back room and when I saw all the colours it was love at first sight. I never took up the apprenticeship with the BBC."
Still, there were no training courses so she had to teach herself as she went along. "My mother, bless her, lent me her front room and I used to get all the neighbours in. I had some terrible disasters. But it earned me pocket money and it taught me confidence."
When the salon closed in the late 1960s, she moved on to Vidal Sassoon, which is when her career really took off. "It was magic, working with the master. The energy, the adrenaline, it was amazing. I never wanted to leave. Everybody came to Sassoon: Vanessa Redgrave, Catherine Deneuve, Sharon Tate. I did a lot of film work too – David Hemmings and Richard Burton. And Tony Richardson – once he clocked on to me, he would always ask me to work on his films, which was a great compliment."
But with all those big heads in one room, didn't things ever get a bit – er – hair-raising? "Only the C-lists have demands," she insists.
"All the A-list are lovely – they're very professional, grounded, unpretentious. It's no big deal. It's all the Bs and Cs who think they're amazing. They're a pain in the bum, really. In fact, I've had to get rid of a couple of people. I just said, 'I'm sorry I cannot do this any more.' It's not worth it."
However, even after 40 years in the business, she still relishes a challenge. "I had a lovely girl who came in with very thick, long brown hair with a fringe and she said, 'I want to look like Bree from Desperate Housewives.' I was like, 'Yes! Fantastic!' I couldn't believe my luck."
But those who want to bring a touch of drama to their hair this year might be disappointed. "More solid colour is coming into force this year, rather than great chunks of streaks," says Hansford. "It's all about shine, condition, grooming. Cuts are as important as colour, but this season it's really nice, sharp haircuts – lots of bobs, and the fringe is back in again too."
Due to popular demand, she has launched her own range of hair products, the latest of which is a leave-in spray conditioner, which will be on the shelves next month. "If you put volumising shampoo on your hair then put conditioner on it, you're flattening it all down and destroying the effect," she says. "But with this, you just spray round the edges, comb it through and leave it."
The range has met with high praise indeed. "We had an e-mail saying Sienna Miller loves it. Hurley loves it, even Camilla loves it. That makes me feel confident."
Jo Hansford hair products are available at Harvey Nichols and John Lewis and online at www.johansford.com
• This article was first published in The Scotland On Sunday, April 25, 2010