Sienna, who was recently voted one of our top festival style crushes, looked radiant in a strapless Burberry dress, skyscraper nude heels, and a cute floral headband.
And while we loved her elegant frock, it was Sienna's glowy make-up which caught our eyes the most.
We're used to seeing the mother-of-one channelling an au naturel beauty look, so we were surprised by Sienna's choice of sultry berry lippy and mega-watt lashes.
Here's how to get her fab new look!
1) Sienna kept her eyes pretty simple for this look, so add subtle definition to your peepers by lining the upper lash line with a matte black eyeshadow. Curl your lashes, then add several coats of mascara.
2) The focus of Sienna's look was her vampy plum lipstick. Deep colours are tricky to apply, so start by lining your lips with Rimmel 1000 Kisses Lipliner in Black Tulip, £2.99, before lacquering your pout with the PIXI Tinted Brilliance Balm in Bitten Berry, £12.
3) Despite being famed for her English rose complexion, Sienna amped up the glamour by flushing her cheeks with a golden bronzer. Dust the 2true All Over Natural Bronzing Powder in Matte Bronze, £1.99, on the apples of your cheeks and underneath your cheekbones for a contoured look.
4) Add a touch of glow to your look with a liquid highlighter, such as the No7 Skin Illuminator Radiance Boosting Beauty Fluid, £11. Using your fingers, dab across the very top of your cheekbones, down the bridge of the nose, and around the inner corners of your eyes for a wide awake look.
What do you think of Sienna's new make-up look? Let us know by commenting below as the best comment across the site each week wins £50!
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