Of course, the London It Girl would make it on our list. She spawned a mini army of ombré locks and made us fall in love with bedhead all over again. Alexa may seem like she doesn't put any thought into her mane, but we know better. Who else could start so many trends, or even pull off a messy ponytail so gracefully? Just goes to show you that great hair doesn't have to be perfect or groomed into submission to look mind-blowing.
Photo: Picture Perfect/Rex USA