Buy the tightest pair of pants you can find. Then when they are too tight, eat less.

I was partly joking and partly serious saying that. For years I decided not to break down and buy a larger pair of pants. That helped me from eating too much. But, will power on caloric intake is best.

The key is that everybody has their own caloric requirements and that varies for differing amounts of exercise. I try to keep to a 2,700 to 2,900 calorie per day range which works for me on avoiding weight gain during summer, maybe 2,600 calories per day in winter. A lot of people will gain with these numbers, I think my basal metabolic requirement numbers are closer to 2,200 calories per day but I am active enough to burn the rest thru exercise every day.

There are several on line sources of calorie tracking data on the internet. I do not keep track of my data on the internet, but I know some bikers that do. It is getting easier to do that now that smartphones allow people to update their data almost anytime and from anywhere.

I have a friend that will sit in a restaurant and update his data on his phone before he orders a meal, that helps him decide what to eat. But, he was in the emergency room for some heart work recently so I do not know if he will stay that obsessive on his food tracking months and years from now.

I have used this site to look up calorie data and it also can track your calories.
http://www.livestrong.com/myplate/