What do you mean you have a hard time getting your nutrition right? Are you deficient in some particular nutrient? A well-balanced diet of lesser-processed fruits, grains, meats, and vegetables should provide all of your nutritional needs if eaten in responsible portions.
I think it depends on your goals. However aiming for .8-1 gram of protein per pound of body weight is a good place to start. From there fill in carbs and fats to meet your caloric goals for the day. Hope that gives you alittle help!