I spoke about the importance of getting your energy balance right. The next thing to nail down is your ratio of macronutrients, and by this I mean how much protein, carbs and fats you are consuming on a daily basis.
Out of the 3 your main focus should be on protein first (protein actually means of prime importance). Trying to achieve a consistent amount each day. How much I very individualised! A good starting point for a non active person would be between 1-1.5g of protein per kg of body weight. An active person then trying to achieve anywhere between 1.5-2.5 depending on what activities they are participating in. This can even go up to 3 per kg for competitive bodybuilders!
Next is getting your carbs and fats right. This again is very individualised, however a good rule of thumb to go by is a very active person should be consuming a higher carb to fat ratio due to the more higher intensities and durations demanded and vice Versa for a not so active person, due to energy systems being used.