One rule to a flat stomach?

dont eat !!!!!!!!

and excersize daily :D

NOOOO you NEVER should not eat, it will not help you at all!!! it will make you MUCH less healthy than the condition you are already in! if you want to SAFELY lose weight in a HEALTHY way, then you should excercise daily (not too little because nothing much will happen and not too much because that will become dangerous for you) and have a healthy diet. A healthy diet does NOT mean that you skip meals and it does NOT mean that you have a gazillion meals or even 3 humongous ones. You must eat 3 times a day but make sure your diet includes lots of veggies and some fruits (not too much of those either--they have some sugar, believe it or not). Also drink PLENTY of water. Often your body confuses thirst with hunger and when you really have eaten enough already, sometimes you feel you need more because you are thirsty. If you drink a ton of water and try to have a fruit at the end of your meal then you will feel very satisfied.

It shouldn't be painful to lose weight. If it is, that's a bad sign. Now, don't confuse pain with exertion--it takes a work ethic to get slim, but don't hurt yourself doing it!