One of my non-negotiables is writing in my food journal. As soon as I stop, I lose insight into my eating habits and I start getting off track. Studies found that people who keep food diaries wind up eating about 15 percent less food than those who don't.

There are many apps that you can use nowadays too if you don't like the traditional paper and pen. I've used MyFitnessPal for many years which I like. The most important thing is to document is somewhere so that you can go back an analyse the data.