Sandie Shaw is wriggling and giggling. Now she’s sitting cross-legged. Now there’s the laugh that hits the ceiling. And more wriggles. And lots of funny voices. If you didn’t know she hated the song, you might say she was acting like a bit of a Puppet on a String. But she’s just recorded an interview with Jonathan Ross, and she seems to be quite high. Grace, her lovely-looking and, at 20, her eldest child, has just left us. (‘Yummy Mummy’ is what her children call her.) ‘Grace is really beautiful, not just physically but mentally and spiritually. We relate very much to the child in each other as well as the woman.’

Sandie Shaw came back after an absence of more than 15 years-‘my black hole, I call it. I don’t know the exact dates’. She ‘retired’ at 24, pregnant and with 17 hits behind her. Always Something There to Remind Me… This is the girl who came from Dagenham and whose first job was with the Ford motor company, training to be a computer operator. She who finished her marriage to dress designer and television presenter Jeff Banks in poverty and went to work in a restaurant in Soho where, once Warhol’s guest, she found herself waiting on him. ‘I didn’t feel ashamed. I loved it. It was such fun.’

Sandie Shaw is clear-complexioned and bright-eyed (penetrating blue and ‘blind as a bat’), with curly lashes, rich brown hair, little-girl dimples, architectural cheekbones, and what is probably a willowy figure beneath the billowing pink T-shirt. Grace’s mum, in other words. She’s wearing lurid-fluorescent, even-green Ozbek leggings and the trademark bare feet are shod with lime running shoes. ‘I might be sophisticated from the neck up, but from the neck down . . .’

The eternally youthful 44-year-old (on being asked, she says she’s about my age; I’m 31) who has just published The World at My Feet takes a sip of her white-wine spritzer.

She left singing so prematurely ‘because I’d buggered up my career’. She was, she reckons, slipping artistically and soaring commercially. ‘I’d done some really great stuff-and then I was talked into doing this crappy song Puppet on a String and entering the Eurovision Song Contest. I didn’t know what a feminist was then because they didn’t exist. But instinctively I knew it offended my sensibilities.’

She walked off live German TV when they played it. (‘I don’t want to wallow in nostalgia, it’s so negative. It’s valuable to look in your wing mirrors from time to time, just to know where you’ve come from. But you shouldn’t drive like that, without consulting the road ahead.’) ‘There were hits after that, but nothing I enjoyed.’ The turning point, she says, was this bloody song where they kept changing the lyrics and it was in Italian. ‘I went and hid in the gazebo in the garden and covered myself in hay and waited till everyone went away.’

Any fool, she reckoned, could get up and sing. But the book reveals she was looking for an inner conviction, having spent years ‘winning publicly and losing privately’. Her self-confidence is fragile. She’s known what it is like to ‘descend into the pit, to live in the dark, airless basement, to be traumatised by pain, to be paralysed by fear . . . sometimes life kept hitting me so hard that I would crawl around on all fours unable to stand up. For days I hid under the smoked-glass table top, curled up foetus-like’. Grace-who held her mother’s hand at the births of her next two children-would pass her her meals, sometimes forcing her to chant. Did these Dark Ages continue throughout her ‘retirement’? All through her marriage to Jeff Banks? ‘Oh no. That sounds awful. But that whole time (10, 15, 20 years, she doesn’t know which) I lost my direction, my self-esteem, my money and I lost a baby. I’d lost just about everything you can lose. And look at me now.’ (Giggle giggle and she’s putting on silly voices again.) ‘I needed to get away from everything. I had no respect for myself as a woman, artist, human being, person of talent . . .’

So why did she write the book? ‘Cos I was in kind of a unique situation. I realised I was getting these kind of parallels of everything I had lived in the past and not done quite right. So I thought I’d resolve it in this new situation. Every day seemed like a second chance-every relationship I had, my re-emergence. It was all a kind of reliving of something.’ Meet Sixties Person. Mrs Time Warp herself. She who used to ride a tricycle and, it is said, breast-feed in interviews. She who, along with Jean Shrimpton, Mary Quant and Twiggy, was the inspiration for a generation; a household name in Europe and the pin-up of every mod astride a Lambretta. ‘I think I’m a very Nineties person. I really do. The things I carry from the Sixties are really right on. Things like being spontaneous, really connecting with the whole, the universal-consciousness thing, the peace initiative. But I think I’m always in the eye of the hurricane. I’m always in the middle of what’s happening.’

But don’t ask who it is inside the hurricane. We’re not allowed to grasp her essence. You see, we can fuse (her words) at a particular time, but we can’t capture her. She changes from moment to moment, and it’s like we can’t read her personality-just pick up (still her words) certain nuances and atmospheres. ‘It’s just like I’m so multi-textured. I mean that’s what’s so great about people.’

Her mother, in The Sunday Times in 1965, described her as ‘quiet, reticent . . . she was quite a lonely child. She used to like her own company . . . I’ve tried to teach her to be good and believe in God’. Which brings us onto her Buddhism. Sandie Shaw is another singer-Cat Stevens, Cliff Richard, Aretha Franklin-with the religious impulse. A dedicated Buddhist who works as a district leader for central London for the Nichiren Shoshu brand of Buddhism-Tina Turner, Lynn Franks, Herbie Hancock-she chants daily. (Nam nyoho renge dyo . . .) It improves the tonal quality of her voice as well as giving her an inner calm, balance and happiness. ‘It makes the quality of my life fantastic.’ She started in 1977 and has gone on record as saying she has been able to change everything she doesn’t like about herself. But as to what she didn’t like . . . well, that sort of thing changes from moment to moment.

But why? ‘I’m quite prone to lose my confidence. And I understand now more what triggers it. No, I won’t tell you. That’s between me and me. But I think people are unique and each person’s karma is so theirs.’ What sort of childhood did she have? ‘Some of it was happy, some of it wasn’t. You can’t grasp someone’s personality in a moment . . .’

Why did her first marriage go wrong? (She is now married to Palace Pictures film millionaire Nik Powell who proposed on their first date and married her in the Buddhist Centre.) ‘I don’t think that particularly matters. I think what is important is why my second marriage is succeeding.’

So why did she re-emerge into the public eye? (‘Did I let Nik know I was going out?’ she writes about her thoughts on her first tour. ‘Have I left the kids something to eat? Did I leave the washing on?’) ‘I was dragged out of my shell by lots of people who said I was wonderful. And they said it often enough for me to start believing it a bit.’ Right at this moment, perhaps she is.

Then I was talked into doing the Eurovision Song Contest… it offended my sensibilities