The key to healthy quality weight gain is to eat big and eat consistently throughout the day following a structured meal plan.
Aim to eat six or seven high protein meals / snacks per day. Include plenty of high protein food choices, like lean meat, chicken, fish, eggs and milk; high fibre complex carbohydrates like cereals, bread, pasta, rice and potatoes; and fruit and vegetables (don't forget nuts and pulses are also good sources of protein).