Eat more fruits & vegetables. Not only good for you, but most vegetables and some fruits are also low in calories. Plus, they contain fiber to help you feel full.
Watch portion sizes. Enjoy your favorite foods, just enjoy less of them. If you cannot 'eat just one' then save those foods for special occasions.
Plan ahead. Deciding what to order at a restaurant or bring for lunch beforehand takes the guess work out leaving less room for temptation. Plan frequent, small meals/snacks to keep you from getting too hungry.
The Surgeon General estimates that overweight and obese Americans spend $700 more a year on medical bills than those who are not overweight. Healthy eating along with physical exercise can help you maintain a healthy weight.