Diane von Furstenberg: 'I danced at Studio 54. Now I work with Google'

It is completely impossible to interview Diane von Furstenberg. It is almost as impossible to meet her without falling just a little bit in love with her. The first, because it is not in her nature to follow another person's lead, whether in conversation or in anything else, so instead of answering your questions she just tells whatever tale from her fabulous life she feels like telling; the second, for much the same reason.

We are sitting together on a yellow velvet sofa in the penthouse suite of a smart Munich hotel, balcony doors open to a breeze drifting in over the red gothic rooftops. She puts her glasses on to get a better look at me, then leans back and props her feet – nude fishnets, high-heeled sandals – on the coffee table, and tells me about the time she told Oprah Winfrey that as a little girl she "didn't know what I wanted to do, but I knew the kind of woman I wanted to be – an independent woman, who drives her own cars and pays her own bills" – and how Oprah loved the story so much that Von Furstenberg has named her forthcoming memoirs The Woman I Wanted To Be, "because if Oprah thinks it's important, it's important, right?"

Then she tells me about the time she was having breakfast with Anna Wintour. "I was having a lousy day, and I asked Anna: 'Do you ever have a day when you wake up and feel like a loser?' And she said: 'Sure, all the time.' Which made me feel a little better ..." And then she tells me about the first time she posed for Andy Warhol in 1973, and how he wanted a white background and her apartment was all colour and print, so she squeezed into the only white space available, in the kitchen next to the refrigerator, and there wasn't room to stand straight, which is why she is posing with one arm twisted above her head in that picture.

It is the Warhol connection that brings us to Munich. Von Furstenberg is the first in a series of Designer Conversations, curated by the MyTheresa.com fashion boutique in order to give their online fashion consumers a look into the minds and lives of the people behind the brands. The evening after our afternoon on the sofa, MyTheresa's creative director, ex-Grazia fashion editor Paula Reed, will host a dinner in Von Furstenberg's honour at the city's Museum Brandhorst, home to over 100 Warhol pieces in its permanent collection – and, in honour of DVF's visit, a pop-up display of wrap dresses in the foyer. There, Reed will remind the assembled guests – German Vogue editors, minor European royals, DVF staffers – how Von Furstenberg "participated in every pop cultural moment of the past 40 years, built her business from scratch not one but three times, and all while raising two children."

The DVF story is fashion's favourite fairytale. The free-spirited young European princess who arrived in New York in the early 1970s and made her fortune with a dress, was on the cover of Newsweek before she was 30, then lost her way in business, moved to Paris, divorced and remarried, staged a comeback in her 50s and now helms a business more successful than ever, with 85 stores worldwide. The year 2014 is yet another significant date, in a life with more than its share of landmarks. The 40th anniversary of the wrap dress has been celebrated with an exhibition in Los Angeles, and November sees the publication of her memoirs.

"The wonderful thing about ageing," she says, "is that you have a past. In fact the only thing I don't like about ageing is the way I look. I don't wear a wrap dress any more, because I don't have the waist, and I don't like that." Actually, she looks great. She has fabulous legs, and the kind of face that hollows with age rather than sags, so that her fine bone structure is even more striking than when she was young; she softens the effect with a halo of coppery hair and lots of glinting gold jewellery, all of which enhance her deeply tanned skin. She looks amazing, and I tell her so. "No. It's not true. I don't look amazing. But I haven't touched my face." Really? Nothing? No Botox, no fillers? "No. Nothing. I haven't done anything at all, which is why I look how I look. But apart from the looks, I get better. I'm smarter, I'm more aware, I'm kinder."

The wrap has stayed alive and relevant for four decades because what it stands for – a woman dressing for freedom and movement and self-determination – is as compelling now as it ever was. In the early days, Von Furstenberg airily extolled the joys of a zipless dress which you could slip on quietly when you wanted to make a swift exit without disturbing a sleeping man. That boldness still feels ahead of its time in 2014, when the "walk of shame" is the butt of many a joke. "That's what my brand does," she says. "We sell confidence." Confidence comes from comfort, as much as from glamour. She notes that it is female designers – "Coco Chanel, Donna Karan, me" – who dress women in jersey, "because we know it feels great and lets you get on with your day, and we care about that." She is a unique combination of being ultra-feminine with a distinct feline slink to her walk, but comfortable being in charge and entirely without coquetry. In the introduction to her book, she tells how, as a girl revising for exams, she would pretend she had students, and imagine herself teaching them. Passivity bores her; what's more, she says, "idleness breeds insecurity. It's so important for women to have children but it is equally important for women to have an identity outside the home. You have to be engaged, you have to be part of the world. … It doesn't have to be a job. It can be that you bake [sic] the best jam in the world and everyone wants a piece of your jam. What matters is doing something."

For most of the wrap's 40 years, Von Furstenberg "took that dress for granted, even though it paid my bills, paid for my children's education, my apartment on Fifth Avenue and my house in the country. To be honest, sometimes I even resented it. But now, finally, I see: this dress is actually bigger than me. I am just a conduit for the dress. … It is so much the essence of my brand. I became who I am, because of that dress, because the dress is everything my brand stands for." I want to ask her about her own memories of the dress, but she starts to uncross and recross her legs, an impatient gesture I have identified as a "tell" for not-interested-let's-move-on, and then she starts firing questions at me instead; how old am I? Do I have children? How old are they? What does my editor think about the (recently announced, just minutes before our interview) acquittal of Rebekah Brooks?

She has recently appointed Michael Herz, a British designer initially hired to curate the wrap dress exhibition, as artistic director of her label. "I am working on adding great talent and professionalism in all areas of the company. I thought I would retire by 30, and I'm 67 and I'm working harder than ever. But that's because this is the last stage of my work. I have built something big, and now I need to carve the DNA really deeply into it, because I am planning for a time after me." Is she talking about retiring? A change at DVF – whether a stock-market flotation or outside investment – is rumoured to be on the cards, but fashion designers are sensitive on the subject of retirement. (Giorgio Armani, 80 next week, refuses to discuss the notion.) She demurs. "Well ... it's not about retirement, right now the company needs me, but I am planning for a time after me. I am very involved in my women's causes (for six years she has been active on the board of Vital Voices, a global organisation to support female leaders) and that will never stop. That, I will be doing until I die."

Last year, she wrote an article for the New York Times celebrating the digital revolution. "Sometimes people my age still say: 'I don't do email, my assistant handles it,' and I tell them: 'You can't say that. It ages you.'" She has an iPad with a DVF chain-link cover (she proudly shows me the Guardian on her Newsstand) and an iPhone case with inbuilt knuckle-duster, with which she snaps photos of my blouse – a vintage DVF twig-print in apple green – and emails them to her team in New York. "I am so lucky," she says. "Old enough to have danced at Studio 54, young enough to be involved in the first design collaboration with Google, when we did Google Glass." Working on the 40th anniversary 'Warhol' editions of the wrap dress made her think about "how Andy Warhol was a visionary. The world of branding, the iconography of the modern age. He was so, so far ahead of his time. He was making reality shows, decades before anyone else knew what they were. Can you imagine what he would have done with Instagram? Those were extraordinary times, the 70s. As exciting as right now. Not more exciting, though. Now is great."