What can I do to minimize the effects of food coma other than eating less per meal?

Easy does it. Eat smaller, frequent meals instead of 3 large meals. Eat less fattening foods. Don't relax after eating; go for a walk.
Lay off the carbs. The so-called "food coma" is a byproduct of Insulin secretion by your pancreas in response to the carbohydrates you eat in a meal. The Insulin allows your body to absorb blood glucose into your organs and muscles, but can also cause drowsiness as your "rest and digest" reaction to food kicks in. Fight food comas by eating lighter meals that are less carbohydrate-rich, and exercise daily.