Sienna Miller must travel with an invisible personal lighting crew. That’s one hypothetical explanation of how, on an unseasonably grey day, she’s gleaming and beaming and standing to shake hands like someone out of a very upmarket holiday brochure.
It’s nearly impossible to envision Miller as ever having been less than entirely self-possessed and glossy of mane. But there was such a moment, she insists.
‘I had cornrows on holiday, with turquoise beads at the bottom,’ she says of her biggest beauty faux pas. ‘I turned sixteen and I did it on my sixteenth birthday and I had braces, and cornrows and a sunburn on a beach, and it was probably the most unattractive moment of my life. It’s documented,’ she grimaces. ‘My dad keeps threatening to bring out the photos.’
We’re here because Miller is promoting BOSS Orange’s new limited editions benefitting UNICEF. ‘My first fragrance was Hugo Woman,’ she says. ‘It’s such a personal thing, a fragrance, but it’s how it makes you feel, and this is a particularly uplifting and joyful and youthful fragrance.’
Sales of the limited edition fragrance fund school fees for children in Madagascar, with the goal of educating 60,000 children. ‘The initiative is fantastic and it’s wonderful to be able to be part of a fragrance that is conscious in that way,’ she says.
Beyond the fragrance, Miller’s major focus at the moment is her impending motherhood. She’s expecting a child with partner Tom Sturridge and pats her tidy bump throughout the conversation.
‘I think having a child is one of the most fulfilling things you can do as a human being, and I imagine that a lot of unanswered things will suddenly make sense when you realise that there is something significantly more important than yourself,’ she says. ‘So I’m looking forward to experiencing that.’
Maternity dressing has posed a challenge, even with sister Savannah and fashion friends like Matthew Williamson and Tabitha Simmons to call on.
‘You just don’t feel particularly elegant,’ she says. Although she has tried not to succumb to maternity-wear, opting instead for larger sizes of non-maternity clothes, ‘I’m tending just to opt for comfort at this point.’
She owns ‘ludicrous’ maternity tights and an accommodating onesie that makes her look ‘like a Teletubby’, but which is very comfortable.
Today Miller is garbed in a Breton-striped dress, tailored black blazer and snappy little boots. She also wears a few pieces of jewellery, including a glittery diamond ring, on a finger typically reserved for engagements, that she definitely does not want to discuss (‘It’s just a ring. It’s a vintage ring. I have lots of jewellery on.’).
But back to maternity dressing: ‘It’s a time not to worry too much about how you’re looking.... You try and adapt,’ she says. ‘Stella [McCartney] did send me some really beautiful baby clothes which was very exciting, but nothing maternity.’
Her beauty routine has changed with pregnancy, leading her to take more time for herself and use body oils to prevent stretch marks. She still keeps personal beauty icons Brigitte Bardot and Jane Birkin in mind. ‘[The ‘60s] was a really amazing time and I’m drawn to that style, and anyone who’s not too overdone.’
Miller recently had the chance to embody another of ‘those really iconic ‘60s beauties’ by playing Tippi Hedren in The Girl, a BBC film. ‘She’s an incredible woman and I admire her hugely,’ Miller says. Hedren, a Hitchcock blonde and star of The Birds, is, like Miller, extremely private, shunning Hollywood in favour of conservation and animal-welfare work.
‘Trying to emulate her grace was challenging because she was incredibly dainty and elegant and I can drag myself around, and she can glide,’ Miller says. ‘So that was something I had to really work on.’
And the invisible lighting crew beams on...
More from Sienna’s life in beauty
Makeup bag essentials: Givenchy highlighter and Hydra Sparkling Magic Lip & Cheek Balm, NARS bronzer stick in Palm Beach, Dr Hauschka Blackthorn Body Oil
Beauty rules to live by: Sunscreen. ‘For years I never wore anything. I would lie in for hours full-on in the sun, and now I have extra freckles everywhere, so I do wear sunscreen. It’s the only rule I have.’
Top hair tips: ‘I tend to leave my hair alone and therefore it looks messy.’
Her top pros: Lester at John Frieda and Amy at Daniel Hersheson for highlights; Una Brennan and Yvonne Martin for the odd facial.