15th birthday party theme ideas?

I want to please my self and my friends. Some of them are really preppy, but others are more unique. So, basically something that I will like, but my friends can still enjoy it. I'm really girlie, but I want an unique theme. I like bows, mermaids, polka dots, Paris, fashion (I want to be a designer), Glee, fairy tales (yes, still), nail art and polish, and anything sparkly.