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Fake the flat iron

Works best on: Straight hair

How to get it: You might not have a flat iron (ha, who are we kidding?) but you can still get Sienna Miller's look by teasing your hair.

1. Just let your hair dry naturally, since you'll want it to be a bit poofy for this look. Once it's dry, brush through it well using a boar bristle brush.
2. Tease your hair in sections: lift up the top layer, mist with hairspray and tease downwards with a teasing comb.
3. Mist your hair with a frizz-minimizing finishing spray to keep flyaways under control.