Sienna Miller's top style tip is to make sure you have a "great pair of jeans" because they can "elevate" any outfit.
Sienna Miller has shared her top style tips
The 42-year-old Hollywood actress has opened up about her fashion must-haves revealing she always sticks to her favourite denim which she teams with a good jumper and nice accessories.
She told Stylist magazine: "I have quite a clear aesthetic of what works for me. I think a great pair of jeans, shoes will elevate any outfit, a great jumper.
"I tend to wear a lot of jeans, and then earrings and accessories or a nice watch."
Sienna added she has quite an extensive collection of knitwear and she loves one particular jumper - from high street store Reiss - and her 11-year-old daughter Marlowe often borrows it.
She explained: "I like to buy knitwear. I have a great jumper from Reiss (a crew-neck mid-grey cashmere jumper) – you’d never know it wasn’t The Row. It’s a perfect jumper. My daughter nicked it and looked amazing in it."
The actress went on to add she thinks Brits have an incredible sense of style because of their "irreverence" and "humour".
She told the publication: "There’s no one that does undone, relaxed chic like the Brits; it’s something to do with the irreverence of being English and the humour, there’s just something about British style."
Sienna was speaking at the launch of her Marks and Spencer collection which has taken inspiration from her own wardrobe as well as redesigns of some classic vintage pieces.
She previously revealed the capsule collection for the British high street giant is very much what she "likes to wear".
She told Harper's Bazaar magazine: "There are about 20 pieces. Essentially, you could pack that range in your suitcase and you have a holiday wardrobe. "It’s a combination of things from my own wardrobe and things that I wanted – vintage pieces that I redesigned. It’s very much what I like to wear.
"I do have an aesthetic."
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