Eat at regular intervals. If you can, try to have your meals around the same time each day. Eating on a regular schedule helps your body settle into a pattern that allows it to burn the right amount of calories. If your eating habits are unpredictable or you're prone to skipping meals, your body will tend to hang onto calories for an emergency.
A regular food schedule can also help you mentally control your eating. If you have a set mealtime to look forward to, you can give yourself an exact timetable for delaying gratification.