How do I get rid of my stomach fat? I'm at age 14 FYI [:?

Well I really have no idea to help get rid of it, but I've heard that if you keep your stomach sucked in for several mins at a time, it builds the muscles in your stomach to where you automatically have a smaller/flatter stomach, and I even do it and it actually works! Also using one of those exersize ball things you can buy. I'm 14 too, and I'm trying to get my stomach flat for swim suit season as well!