That's a question many people would be asking themselves as soon as they start noticing the belly become big, when they start feeling heavy and are panting when they walk, that's when the panic mode sets in. I know i have been there before, though i like to keep fit, sometimes i just feel out of the weather and get lazy to do my exercises. Anyway the easiest way to do this, start by doing little exercises like walking around the neighbourhood for at least 30minutes everyday, or jogging. If you cannot jog get a nice skipping rope and skip a little each day, that should keep you in check. You can also download aerobic exercises on the net and do them in the comfort of your home at your own pace. This is out of experience i have done it and am still doing it and its very effective. Another way you can go about is by doing zumba exercises they are not just done by women but by men too. You should try them and see how your body is going to be toned up in a matter of time. It has worked for me over the years and i believe it can work for you too. Eat healthy foods as well because if you do exercises and not eat well it will of no good.