1. Eat healthy : Include food of all colours in your diet. Body will gain weight vastly if you take proper healthy carbos, fats and proteins.
2. Increase calorie : Eat healthy food 4 or 5 times a day. Take more calorie in meal than you have consumed in whole day. Body would start gaining weight.
3. Build muscles : Weight lifting exercises help in building muscles. Plan your exercise schedule with the help of experts.
4. Milk and honey : Take milk with 2 teaspoon honey in it before going to bed. It will improve digestion and increase weight.
5. Butter : Eat half teaspoon butter with sugar daily. Body will get proper saturated fat and calorie, weight will increase.
6. Curd-sugar : Add sugar in bowl full of curd and include it in your meal. Proper calorie would get and weight would be increased.
7. Peanut butter : Eat peanut butter with bread in breakfast. it will give energy to body and helps in increase weight.
8. Eat potato : Potato contains proper carbohydrates and complex sugar. The weight will increase if potatoes would add in regular diet.