Simple, just don't eat too much (don't go for extra servings n shit), especially at night. Don't eat, just to eat. That's a big problem after night life, people like hitting up 24/7 Taco shops, Denny's,etc... avoid that. Avoid junk foods. Not that you can't have soda and chips once in a while, but cmon, not everyday. Keep yourself moving and exercise. If exercise like running bores you, go to the mall, beach and just walk around. You'll be burning calories all while looking at chicks.
I haven't tried this, but try using smaller plates and utensils. Try smaller kid forks/spoons and plates. Or just experiement with the smaller utensils. Should force you to eat smaller servings and slower. The slower you eat, the fuller you feel. This might train your body into eating less and feeling just as full. Just an idea, but a good one I think. It's all mental.