People today imo are taking everything too literally in the way of eating & training.The old timers had it right imo when it came to eating to get big.Foods such as whole milk,lean cuts of red meat, whole grains, veggies, fish, eggs etc. are what will put the ponds on you quicker than anything.Also, a high water intake alone can actually put a few pounds on you if you don't have a high water intake & your body is depleted of it.If you see your gaining fat you simply cut down your caloric intake.Essential fats imo can also help your body in staying lean.It's all in keeping the whole picture in moderation & actually quite simple.As to training it's the compound exercises that you gain size with.No sense in a skinny kid doing leg extensions in place of squats.Actually I see no sense in an ectomorph doing any shaping exercises period.Stick to the mass builders & you will gain as long as your food intake is also good.