Add calories: Although not in an unwise manner, the essence of gaining weight is eating more than before. But you should plan your meals in a way that helps you gain lean mass and not fat. Assorted nuts, milk, cheese, high-calorie fruits such as banana are some of the foods that are very useful in helping you gain weight.
Strength exercise: Weight training is an important part of gaining weight. This may sound ironical to some but it is true that you need to be able to use up the excess of calories that you are consuming. This can be achieved by working out. But make sure that you give your body enough rest too. So, working out three days of a week is recommended.
Starchy vegetables: You should choose starchy vegetables so that more carbohydrates are consumed. These include corn, potato, and carrots. Veggies such as celery and cucumber are too watery and do not help you gain weight. They can be taken as appetizers though, but not as the main course.
Have more proteins: You need to increase the amount of protein in your diet. This is for obvious reasons. You are working out and it is important that the additional calories that you consume get converted into muscles and not so many fatty formations on your body.
These tips should tell you how to gain weight and it is advisable that you set about following them right away. Your body of dreams is only a few months away if you follow these steps.