It's amazing what cutting back on junk food does for your body. just by removing most of the sweets you eat and eliminating soda (or using the 0 calorie stuff to trade fat for cancer) you will lose a ton of weight.
Smaller portions really helps, too, even when eating fast food. Eating frequently throughout the day but only having a little bit helps tremendously. Don't order a combo, order a larger sandwich. Instead of two burritos, get a loaded one so you don't get 200 calories from another tortilla.
Just don't starve yourself. Back in december I got a little anorexic after a terrible diet of junkfood, and the truth is you can actually stay the same weight, or be even slimmer, by eating non-starvation quantities. But if you starve yourself you'll balloon up if you have a carrot too many.