Oh no! I'm having guy troubles!?

HELP ME!!! There is this beutiful guy at my school, and i really like him. I know alot of you would say "size doesn't matter" but i am "not the skinniest girl on the block" aka "i'm fat". If you don't know the answer, plse look it up on google or something, but I need some tips that will help me lose weight. We have a Christmas break comin up and i want to look bran new. HELP!