The former Made In Chelsea star took a quick selfie while making her way around London this morning (5 March), showcasing her fabulous FOTD (that's face of the day!)
Gorgeous Mills flaunted her usual flawless, glowy skin with a hint of rosy cream blusher on her cheeks (Millie loves NARS The Multiple in Orgasm, £30, for a fresh glow).
She also opted for petal pink lips and filled-in brows, sweeping her caramel locks back before adding a black headband.
But our fave part of her look? Her perfect 60s-inspired eyeliner!
Now, if you're not a make-up artist like Millie then liquid liner can be hard to perfect, so we've put together a few tips for the perfect feline flick.
1. Choose your product
There are heaps of different types of liners, and it can take a while to find the right one for you. For a very precise line, try a felt tip-style liner with a thin nib, like Pixi Lash Line Ink, £12.
Alternatively, you could go for a liquid liner with a brush applicator like Rimmel GlamEyes Professional Liquid Liner, £5.29. These are great for giving an opaque line, but remember to wipe off the excess product first!
Most make-up artists like to use gel liners which come in little pots. We love both MAC Fluidline in Blacktrack, £15, and Maybelline Eye Studio Lasting Drama Gel Liner, £7.99. You'll need a brush too, and you could either go for a super-thin one like Real Techniques Fine Liner Brush, £6.99, or an angled brush, like MAC 263 Small Angle Brush, £16.50.
If you're a liner newbie, try simply taking your favourite black eye pencil (we like Avon SuperShock Gel Eyeliner Pencil, £6) and apply to an angled brush before dabbing across your lashline. This is one of the easiest methods we've found, and you can trace over the top with a black eyeshadow to amp up the pigmentation.
2. Define your shape
In her selfie, Millie's gone for a line which starts thin at the inner corner before getting much thicker just above her pupil. This shape will help make your eyes look bigger.
If you want to elongate your peepers and give them a feline shape, keep your liner thin along the whole of your lashline before winging it out at the outer corners.
3. The tricky part - your flick!
Start by resting your elbow on a table and look down into a mirror. This will help steady your hand.
When drawing your flick, keep your eyes open and imagine an invisible line continuing from your lower lashline, directed towards the end of your eyebrow. This is where your flick should be. You could even use a ruler or a post-it note to help guide your line.
Once you've drawn both flicks, carefully join them with the rest of your liner to form a triangle shape before filling in.
Make like Millie and finish your look with a pair of false lashes - she's wearing her Millie Mackintosh for Nouveau Lashes in Shoreditch, £8.99.
Do you like Millie's liner look? Let us know by commenting below as the best comment across the site each week wins £50!
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