this beastly guy on my baseball team last year used to walk around school with a gallon of water and a cooler with half a chicken and frozen vegetables... i guess that works. and he would ride his bike 30 miles at a time. and run 10 or 15. basically... just hit the weights (as someone pointed out, less weight but longer workouts are better), run, do agilities (such as sprints, jumps, windsprints) and just eat better. if your in high school i recommend joining track or cross country. helps alot
same as getting buff but with fewer callories. you won't gain anwhere neer as much muscle on a caloric deficit though. do all that but keep your calories down to somewhere between 2000-2500(assuming you have a somewhat typical metaboolism) you should be able to safely loose 2-3lbs of fat a week on this, if you are loosing more, you're in danger of malnutrition. EDIT: i keep forgetting that not everyone has as fast of a metabolism as I, you will likely need to run, I never really need to when I try to cut because of my rapid metabolism(I also only cut about 5% and bulk about 95% of the time, so I am not cutting all too much if you get what I mean, I only have about 7% body fat which is really good[bradpit has something like 10 just to give an example])