Oh, So *This* Product Is How Alexa Chung, Sienna Miller and Kate Moss Get Effortlessly Undone Hair

If you want to achieve perfectly undone hair, then take your cue from Alexa Chung, Kate Moss and Sienna Miller's favourite texturising spray.

A collage with Kate Moss, Alexa Chung and Sienna Miller
(Image credit: Getty Images, @alexachung)

Even with tonnes of hair tools such as hot brushes and curling wands at my disposal as a beauty editor, I actually can't stand my hair looking too "done". Don't get me wrong, I love a bouncy blow-dry when the occasion calls for it. But day-to-day, I like my hair to look effortless and undone, like I just so happened to have rolled out of bed with perfectly dishevelled loose waves.

So it's probably unsurprising that Sienna Miller, Alexa Chung and Kate Moss are amongst some of my hair icons for their perfectly undone hairstyling and piece-y waves. Of course, their hair is expertly crafted by top hair stylists, but it just so happens that they're all fans of one particular texturising spray.

Hair by Sam McKnight Cool Girl Spray

Cool Girl Barely There Texture Mist is one of those products that is exactly what it says it is on the can. Created by legendary hairstylist Sam McKnight MBE (who has worked on everyone from Princess Diana to Kate Moss and Sienna Miller), this texturising mist adds the perfect amount of grit to lengths, boosting volume and texture even in the finest of hair. McKnight was inspired by the effortless looks he's created on Kate Moss, and designed this product with her in mind to help us create the same undone looks at home.

In the above video, McKnight uses it on Sienna Miller, flipping her hair upside down and misting through for effortlessly texturised lengths. Alexa Chung also counts herself as a fan, having previously called it "a gig in a can" for her signature dishevelled waves. It's cool-girl hair in a bottle.

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A photo of Eleanor's hair after using Cool Girl spray by Sam McKnight

(Image credit: @eleanorvousden for Who What Wear UK)

I've been using this product for years and can also attest to its brilliance. If I ever find my curls or waves are looking too polished, I like to spritz a little through my lengths and use my fingers to dishevel as I have above. It helps keep curls and waves looking undone whilst enhancing texture and giving root lift when sprayed around the crown. It's also one of the best-smelling hair products I've tried. In fact, I've had compliments on the scent alone.

Whilst it's not strictly a hairspray, it does offer lightweight hold to styles and brushes out easily at the end of the day—zero crunchiness here. Honestly, if you only invest in one hair product, make it this one. It also comes in a handy handbag-sized travel bottle, which is perfect for top-ups on the go. McKnight, thank you for your service.

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Eleanor Vousden
Beauty Editor, Who What Wear UK

Eleanor Vousden is the beauty editor for Who What Wear UK. She was previously deputy editor at Hairdressers Journal, health writer at Woman & Home and junior beauty editor at Powder. She has also contributed to Wallpaper and Elle Collections.

With a degree in fashion journalism from the London College of Fashion, she has 10 years of industry experience and has been highly commended at the BSME Talent Awards for her work on Powder and also contributed to the title winning Website of the Year at the PPA Awards.

Eleanor’s journalistic focus is providing readers with honest and helpful beauty content. She has interviewed celebrity makeup artists, hairstylists and dermatologists throughout her career, as well as celebrities such as Hailey Bieber, Sarah Jessica Parker and Scarlett Johansson.