want to stop being a fatso? then stop behaving like one.
Step one: set a daily calorie intake limit (~1200 or so).
Step two: there is no step two. congratulations. you're losing weight.
Extra credit: do some kind of exercise.
you can do as much exercise as you want, but unless you're eating right, it's pretty much a waste of time. it's way easier to lose weight by not eating like an idiot.
example: there are 140 calories in a 12 oz can of coke. to burn 140 calories, you have to run a mile at a 10 minute pace. now what's easier? running a mile, or drinking a glass of water instead of a coke?