Only advice I have is tying to cut sugar out of your diet as much as possible. I never eat cookies, donuts, cake, sugared soda (only diet rarely), candy bars, sweet coffee, etc. I have a bit of a sweet tooth and even I can do it (it gets easy after a while). You can't get really fit without exercise, but at least without eating significant amounts of sugar you can prevent yourself from getting too chunky.
Heavily sugared food and drink is the easiest way to massively increase the number of calories you take in per day. It's also the easiest way to decrease it. That's all I'm saying.
I agree with that, I just don't want people here who are trying to be healthier to get the wrong info. It's something I see on a large number of sites I visit, so I try to clarify things like that when I see them. :-)