Eat vegetables whenever possible, just avoid the sauces. If you have foods like carrots, celery, baby corn, broccoli or cauliflower, eat those first. If the options are breads, chips, cheese or sweets, eat them sparingly or not at all.
To avoid binging, make a promise you won't use a plate. Don't eat any more than you can hold in one hand and definitely don't hang around the buffet table. Walk to the other side of the room so you're not near anything tempting.
Tell your friends and loved ones you're watching your weight. You like the food, but you just want smaller portions. If you're dealing with a "food pusher" that keeps insisting you eat more, use stall tactics. Excuse yourself for a bathroom break and don't return to the table when you get back. In larger gatherings people will often forget you skipped the extra helpings.
During dinner, don't load your plate with the stuff you already know you like. Take small portions and sample ALL the foods. You'll expose yourself to new tastes and avoid binging on old favorites.
When dessert is being offered, politely decline and say you're full. Don't give in to food bullies. It's your body and you don't have to eat anything you don't want to. Practice saying "no thank you" and remain firm.
If your host keeps insisting, ask for it "to go" so you can enjoy it later or share with a loved one. Then when you get home you can dispose of it without worry of offending anyone. If there are no other options and you're expected to eat a piece, ask for a small one. Enjoy the flavor and eat slowly.
After the party, get rid of the diet disasters. Foods like turkey can make great leftovers, just make sure to dump the gravy and toss the skin. A turkey sandwich with lettuce, tomato, mustard and fat free mayo on whole wheat is a very healthy meal.
Finally, DON'T plan on starting a diet during the holidays. Simply concentrate on not adding any extra pounds before January and consider that a great achievement.