The fashion blogger was a total stunner as she checked out the online retailer's high summer collection, sporting cute floral co-ords and white strappy heels.
Millie's outfit was new from the Love Label collection at Very.co.uk, with the top retailing at £20 and the skort at £25.
And we couldn't help but notice what an impressive sunkissed glow she was rocking, despite the dreary weather hitting the UK right now!
But while we thought Mills may have been hitting the faux tan, her bronzed limbs were actually all natural thanks to a recent sun-drenched vacay with her hubby Professor Green.
Speaking exclusively to Reveal at the event, Millie said: "It's from when I went to LA, it's natural! I do go quite brown in the sun. It also looks darker because I'm wearing white, that's a great trick!"
Millie - who has her own range of false lashes - also let us in on her top beauty tips for summer, along with her secret weapons for a flawless complexion.
"Tonight I'm wearing my Millie Mackintosh Soho Lashes, £8.99. A good beauty tip for false lashes, if you don't want a really heavy look, is to just cut them in half and apply them on the outer corners.
"I've also got freckles drawn on my face, which my make-up artist did. I think it's a nice thing to do for a summery look, especially if you want to look more tanned. Often when you're tanned your freckles come out, so you can just use an eyebrow pencil in a brown colour which isn't much darker than your skintone, and just dot it on the skin and press it in with your fingertips."
Despite being a make-up artist herself, it seems Mills likes to keep her beauty routine simple by letting her skin shine through without caking on the foundation.
"I like to just wear a tinted moisturiser. I normally start with an illuminating primer like Charlotte Tilbury Wonderglow, £38.50, then apply my tinted moisturiser, and then I just conceal under my eyes or cover any blemishes with a concealer rather than putting heavy coverage all over. I like to keep it quite natural. I use Chantecaille Just Skin Tinted Moisturiser, £58, it's been my favourite for years."
Of course Chelsea gal Mills loves a lavish beauty product, but for cheaper alternatives try Bourjois Happy Light Luminous Serum Primer, £10.99, and Revlon Photoready BB Cream Skin Perfector, £9.99.
"I am quite spoilt with my beauty brands so most of my stuff is high-end," admitted Millie. "But you put make-up on your face every day so I think you want to know it's got good ingredients and it's good for your skin too.
"You can always get a great kohl liner from Rimmel, though!"
The former Made In Chelsea star also has a very exciting project in the pipeline with the upcoming launch of her own fashion line.
But unfortunately for us Mills is keeping her lips sealed for now, saying: "My clothing range will be revealed around August, so that's my main focus at the moment. I've really wanted to tweet pictures of the samples but I've had to hold back. I don't want anyone stealing my ideas!"
What do you think of Millie's summer beauty tips? Let us know by commenting below as the best comment across the site each week wins £50!
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