Tobacco is mainly taken in two forms - either chewed or smoked. In order to abstain or make a person stop taking tobacco the first thing you have to do is motivate him for abstinence. which can be done in a stepwise manner. Educating him about harmful uses both economical and medical burden. You have to make him understand that he is not only staking his health but also money and the future of his family, try to convince him, giving him emotional support for leaving tobacco and when he is ready to stop chewing you can help him by medications like nicotine gum(the way of using it should be properly understood from a doctor) and bupropion (again should not be taken without proper prescription).