Usually I feel bloated when I've had too many carbs.. Maybe try lowering your carb intake a bit, and see if that helps?
Also, some foods (like beans, broccoli, cauliflower, cabbage, sprouts, onions and garlic) are known to cause bloating, so you might want to make sure that you're not overconsuming these foods either.. Other than that, I'd suggest drinking plenty of water and (gradually) increasing the amount of fiber rich foods
hope that helps!