Eat a balanced and normal diet, do regular exercise.

Never starve yourself, it'll just cause muscle wasting.

Also, some people find it easier to stick to either carbohydrates (bread, pasta, potatoes) or protein (meat, eggs, etc), since complex carbohydrates and complex proteins compete to be broken down in your stomach, so the whole process takes long and is less efficient.

That's not say you should ONLY eat one or the other, but trying to keep meals to a majority of one type can often help some people.

But generally, balanced diet, exercise, for the win as they say on the internet.