Don't worry, its very common problem in this age. First of all you have to make you busy in some work or studies or else you can join gym also and avoid watching porn video .Do meditation for mental strength daily to increase your focus and willpower to quit masturbation. Whenever thoughts of masturbation comes to your mind, replace these thoughts by good thoughts by saying or teaching your mind that these thoughts are not good for health and sex. Slowly and steadily, you will definitely win over masturbation. For more suggestion you can consult with us on Lybrate personally.