Eat only excess calories on the days you do weight-lifting. In general, increased caloric intake should be limited to every other day. Avoid extremely large meals. Increase intake by adding snacks or increasing the number of meals on workout days. Consume the largest portion of your calories early in the day.
Balanced meals are a necessity.
Avoid excessive amounts of animal fats, sugars and salty foods. Foods high in these nutrients can lead to degenerative disease. Also, snacks loaded with sugar can kill your appetite for well-balanced meals need to build muscle tissue.