My friend keeps copying me at whatever I wear, listen to, etc. What should I do to make this moron stop?

My friend keeps copying me at whatever I wear, listen to, and more. He is basically a mimic. I used to wear a derby everywhere but when he started wearing one I stopped. Also I used to have a bandana hanging out of my back pocket but now he is even doing it. It works like this with almost everything. Everyone is starting to believe Im copying him because I dont hang around people much. I want to be an individual but with this idiot as my friend I cant be whatever I want to be. I need to know a way to make him stop without damaging the friendship and without making myself look like an idiot. I like the *** kissing and all but I hate it when I hang around him. Is there a way to make him stop without me looking like an idiot and tarnishing the friendship?