I am a huge fan of Lauren Conrad and I have The Hills to blame for that. I didn't pay much attention to her style in Laguna Beach, but her style evolved once she moved to LA. Her style changed from Cali Girl to a relaxed and more feminine vibe. I like it and I admit I've tried to emulate some of her style staples:
Black Headband + Pearls
I was hooked on The Hills after just an episode or two. LC always wore this black headband and oftentimes a string of pearls which forced me to go to the department store and find a black headband that would be very similar to what she wore on the show.
I didn't mind eyeliner much prior to seeing a pretty cat eye on LC (on The Hills, of course) -- I tried to copy this with liquid eyeliner which I had no prior experience with! So there were a lot of days with unevenly lined lids or too thickly lined lids. LC has a cat eye tutorial HERE.
LC always had the most perfect braids which try as I could to copy, it simply can't be done with hair too thin and slippery. Bye to beach waves hair, too.