Fighting frizz can sometimes feel like an uphill battle, thanks to our good friend humidity. Products that claim to do the work for you tend to weigh down and flatten your hair in this weather, which is never a good look. Thankfully, this isn't the case with L'Oréal EverSleek Precious Oil Treatment ($13). Putting oil into your hair may seem counterintuitive (and a little bit scary), but the ones used in this serum are extremely beneficial. Sunflower oils are used to soften your strands, while olive oil improves their strength and elasticity.
But the real winner in this treatment is the argan. This oil gives incredible shine and completely flattens frizz. It's also helpful for your hair's cuticles. Not only does it seal them, making your ends look less bristly, it also cuts styling time down (which protects your hair from heat). Just make sure to keep this stuff away from your roots and to adjust the amount you use if you have thinner hair. Otherwise, you'll wind up with a greasy hairline, and the grunge look hasn't been chic since the mid-'90s.