There's not a one size fits all solution.

The first thing to do is cut down on snacks and sugary drinks if you have them. Refined sugars should be the easiest thing to cut out and will make a huge impact.

If you're already doing that then it's time to start controlling your portions. It will take some will power! I have noticed personally that I may still feel like I could eat more at the end of a meal but that if I wait ten of fifteen minutes then I feel absolutely fine. So focus on eating untill you're not hungry rather than eating until you feel full.

Some people endorse a 5/2 diet, where they will eat normally on five days of the week and then have a very restricted diet on two days (about 300-500 calories). This will recalibrate your feeling of hunger massively, most people in the western world have never experienced real hunger. You may find that what you thought was hunger was very different to actual hunger.

I also recommend replacing your excess eating with something else. All bad habits usually need something to replace them. Whether that is drinking water or learning a new skill or reading a book or doing some exercise. Don't just sit there and suffer, fill that time with something.