If you are going to go off plan, be controlled. You can limit the damages if you follow the golden rule of Extra Easy. Whatever you have, keep to a third superfree.
If you are going to have that chinese, that indian, those chips, those fatty sausages etc, you can still follow the third rule. Whatever you are cooking, bulk in the mushrooms, onions, peppers, on the side have one of those packs of frozen veg that take four minutes in the microwave, chop up those tomatoes, onions and lettuces for a side salad.
Hold an onion in your hand, and then put a tomato in your hand, and a couple of mushrooms, see how much food is there! When you add them to your food as you cook, you are eating these almost calorie free, and certainly fat free foods and filling up on them along with the other stuff.