How to stick to a healthy diet

Cutting out all your favourite foods is entirely unmanageable, so any results you may get while doing so will be not long lasting. Instead, aim for majority of your food (lets say 80%) consistency with your diet, and the rest 20% leave for the times when you go out or you just fancy something "naughty".

Also pick healthy foods you really like. Not one diets fits all people. The best would be to talk to a dietician and make a reasonable and manageable eating plan (yes also the one you can afford).

From my personal experience, I strive the best if I drink plenty of water and snack on healthy snacks in between my lessons. That way I am not running on low of energy. Also eating protein rich food help (including plant based protein as I don't like meat that much). It makes you feel full longer.