Bella Freud is a fashion designer with sharp intellect and a grounded personality. It’s these qualities along with her fixation with the romance of life’s minutiae and a fascination in people – like her father, the late, magnificent artist Lucian Freud – that make her a brilliant person to be around.

It’s nearly 11am on a Sunday morning in February and too cold to be wearing anything that isn’t horrendously ‘outdoors’ or technical. Last night London saw snow and pockets of it remain crisp on lesser trodden thoroughfares – many youngsters too nonchalant to pelt snowballs when they can be indoors BBMing and playing X-Box.

Freud meets Ponystep in Notting Hill Gate, picking us up in her vintage blue Mercedes coupé. She is wearing vehemently destroyed jeans, her own Kingston Pretty sweater and red socks. Her driving shoe of choice? A five inch Céline wooden wedge, particularly commendable given that a pro skier would tread carefully through these slushy streets. Desert Island Discs is on the radio and somehow, within five minutes, Cammell/Roeg’s legendary film Performance, starring Mick Jagger and James Fox, is raised. More layered than an onion, it’s famous for the decree “the only performance that makes it, that really makes it, is the one that achieves madness.” Already there’s the stirring feeling this is going to be a good morning.

Arriving at Freud’s house, which she shares with her husband, author James Fox (not Jagger’s alternate celluloid identity) and son Jimmy, we sit down and drink mugs of tea with their excitable dog Joey.

“I didn’t really know I was getting into fashion,” she begins, softly spoken but impassioned, a characteristic whatever the subject. “I just remember looking in the mirror, aged 10, wearing this scoop neck, puff-sleeve thing. I thought ‘I look stupid, like a pirate’. I recall very strongly being dissatisfied with my appearance. And I knew that with clothes I had the power to change that feeling.”

Freud was always into music – like her son, she is learning to play drums at the moment, a kit sitting proudly in the living room – and hoped she would become “some sort of musician.” It was whilst living in Rome in her early 20s she pursued a career in clothes, catalysed by the nuances and psychology of dress (her great grandfather was, after all, Sigmund Freud). “I love the top tailors and there were all these codes about how many buttonholes you had, whether they undid and if you left them undone what that meant,” she explains. “The very secret language of high-class tailoring, really. And I wanted to find out about it. I reconnected with Vivienne [Westwood] who was in Italy, had an idea of clothes in my head and started making things.”

Freud was interested in Chanel and Saint Laurent at the time. “I remember I showed Vivienne this book about him, she was really puzzled – ‘why are you interested in Saint Laurent?’ I said, ‘It’s incredible, have a look’. She did and was amazed – she saw he’d done this cone bra before anyone else and was knocked out by that. That was a moment.”

Freud’s sister Rose was a punk and that was how the young Bella, aged 16, first met Westwood in England, bagging a job at Seditionaries. “It was great,” she recalls, illuminating. “The best was when Vivienne used to come in with something new – I remember her bringing the Letter to Derek Jarman t-shirt and thinking ‘God that’s so rude!’ Debbie Harry walked past once in a red beret and sunglasses and was obviously too nervous to come in – the shop was empty most of the time because it took a lot to actually make it through the door. She looked fab and we were the most unwelcoming, sneering teenagers. We saw her crossing the road a few times first! Poor thing…” Freud laughs, a shade of horror casting her face.

And like the work of Westwood and McLaren, Bella Freud’s earliest collection had its reasoning. “I always liked the look of the face with a frame to it,” she explains diligently. “I loved collars and I loved school uniforms, things to do with formality that you could unravel a bit. I made these micro-mini knitted dresses with white collars and cuffs. It was all quite concealed but very soft, suggesting the form. You’d get a bit of a flash, the legs and be intrigued. Contrastingly, I always thought the white collar made you focus on the face and the intelligence of the girl.”

Today she continues with knitwear, a perfect medium for playfulness and Freud’s fascination with concept and words – don’t forget she is a keen writer too, penning not only for titles including Ponystep but also blogging for Vogue. “I like the idea of finding a word that somehow is open to interpretation. And that’s quite a challenge, really,” she explains of her emblems. “Take this one, Kingston Pretty. My husband worked for the The Sunday Times Magazine in the 70s, went to Jamaica and interviewed these major gangsters. The government has completely given up and they were running things for a short amount of time. One of them described something as ‘Kingston pretty’, which I thoughts was so great. Words are so important – I remember an interview with Johnny Rotten on TV and someone said to him ‘Why do you hate hippies?’ just as he was walking off. He turned around and said ‘Because they’re so complacent’. I thought ‘Woah’. It was so accurate and perfect.”

Collaboration is also crucial. Freud worked with her friend Christian Louboutin for Autumn/Winter 11. Whereas Autumn/Winter 10 was a joint effort with Susie Bick. In the early 00s she penned a collection inspired by Anita Pallenberg, as well as a fictitious magazine, Memo, with the icon. She has brought success to others too, singlehandedly reviving Jaeger and briefly igniting Biba. Way back in 1991 she created a Super 8 fashion film with James Lebon – a precursor to what is now a recognised format.

“I don’t know why I thought I’d make a film,” Freud says honestly. “I mean now I realise why – I’m obsessed with it. I could get my message across in a much stronger way than I would doing a catwalk. There was no storyboard at all, I just liked the way people dressed at the races, the atmosphere of high class and working class; everyone mixing. If you were pretty and looked good, it didn’t matter where you were from, you could have a moment. So we went to Newbury and did it. But I didn’t have a screening afterwards like you would now – only a stand at London Fashion Week where it was repeating on a TV!”

Freud has realised several fashion films since, three with John Malkovich. Then there’s a powerful photo series, Journey To The End of The Night, by Elle Muliarchyk, which saw the artist trying to get herself mugged (and succeeding). It was exhibited at Frieze Art Fair in 2007. And away from such intrepid creative partnerships, Freud is dedicated trustee of charity Hoping for Palestine.

“In the 70s, certainly in my school, there’d be mothers in twinsets or the worst type of droopy corduroys and Birkenstocks and folk knitted jumpers,” Freud elaborates on her fashion viewpoint back in the car on the way to the Tube again. “I thought this was dreadful, so horrible and an insult  – why should you respect someone who presented themselves as such a cunt?!” she laughs wickedly. “I went to Steiner school and I never wanted to be like any of them. Aside from one teacher who was very old fashioned and has a lot of dignity.”

“I suppose I got into grey flannel through the way my father dressed. He used to have these elegant clothes made in Savile Row yet he was like a rebel and very un-establishment. I love the combination of those two things. Even when he was dressed more formally he looked like he could just jump out of a window whenever he felt like it. I liked that.”

“I was looking around his [National Portrait Gallery] show yesterday that’s just about to open. He spent all his time with these different people, reaching out and getting them to work. How stimulating that was both for him and for anyone else to see the results of. I do like people who are remarkable and what comes out of that really is fascinating.”

It is. And Bella Freud should know – she is a very remarkable person too.