1. FILL UP ON MORE SENSIBLE FOODS
Foods that are high in fiber or water fill you up quickly and help keep you from overindulging on the "bad" stuff. Take an extra scoop of vegetables and fruit when filling your plate, and by the time you finish, you won't have room for the other foods which are higher in calories and more likely to cause you to gain weight.
2. EAT SMALLER PORTIONS
No doubt, everything at the table looks good, and it's all you can do to keep from filling your plate 2-3 times so that you can sample everything. An easy way to combat this urge is to simply take a smaller portion than you normally would of those dishes you're most interested in, especially belt-bursting desserts. Split a piece of pie or cake with your spouse, child, or another family member who may be watching his or her waistline.
3. DRINK AROUND, DURING, AND BETWEEN MEALS
Drink a fair amount of water or other unsweetened beverage before each meal, as well as during and between them. The liquid in your stomach will help trick your mind into not feeling as hungry, which reduces the tendency to gorge yourself on potentially fattening foods.
4. POSITION YOURSELF AWAY FROM THE SNACKS
If you take a seat within an arm's reach of the snack table, you're going to have a tough time keeping yourself from unconsciously grabbing handfuls of party mix, candies, and the like and picking at them all day. By sitting on the other side of the room, getting to the snacks involves a conscious effort into getting up and walking over to get at the snacks.
5. TAKE AN EXERCISE BREAK
If the weather permits it, go out and take a quick walk around the house or block. If your celebration is taking place in a colder climate, you'll be more inspired to quicken your pace and burn a few extra calories in the process. If the weather is bad, do 10-20 squats, stretches, or other brief exercise each time you go to the restroom. You only want to do just enough to elevate your heart rate, but not break out into a sweat. Chances are, no one will know what you're doing, and you won't have to feel self-conscious about trying to maintain your figure.
Finally, if you still manage to put on a few extra pounds, don't stress over it. If you've been following a sensible diet and exercise plan, the chances are good that any weight you do gain is going to come off shortly after the holidays are over.