1. Chew your food 20 or more times per bite
Chewing allows your body to realize that you are eating food, prompting it to create a sensation of fullness at the appropriate time. When you don’t chew enough, you get ahead of that process, eating well past when you are actually satisfied. (Dr. Oz Show)
2. Never eat in front of the TV or while standing
Eating sitting down enables you to be aware of what you’re eating. When you are doing other activities while eating, you will tend to eat faster and more.
Try to enjoy your food, eat it slowly and consciously. And remember that it takes 20 minutes for your brain to know your stomach is full. Also try the suggestions in Trick your stomach full post.