While most people's festival rucksack consists of dry shampoo, denim cut-offs and a few plain tees, Millie's looks a whole lot more luxe.
This morning (15 April) she posted a picture of a headband topped with some of the prettiest (and biggest!) flowers we've seen.
Yesterday, she showcased not one but three leather jackets for her trip along with the caption, 'LA packing... it's leather jacket weather right?'
And if you thought festivals meant flip-flops and wellies aplenty, think again! Millie's gone for two pairs of killer heeled boots complete with studs and sparkly embellishment.
We also spied a chic floppy hat, an across the shoulder bag and more sexy swimwear then a Victoria's Secret catalogue!
Stars like Laura Whitmore and Kendall Jenner have already been snapped at the celebrity-packed Los Angeles festival which takes place over two weekends. We can't wait to see Millie working all her outfits!
What do you think of Millie's festival style? Tell us below as the best comment from across the site each week wins £50!
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