20 Products You Need to Buy the Day You Turn 30

Why: Years of flat-ironing, blow-drying, and curling your hair may have left you with serious split ends and dryness. Remedy that and prevent it from happening again by using a pre-hot-tools protectant serum.

Try: I love Drybar's latest 100 Proof Treatment Oil ($35) because it actually feels nourishing when I add it to the end of my mane. It's like my hair is thirsty and drinking the rejuvenating oil in. I use it after the shower and anytime I need to tame flyaways.