The best way to stop a cat from biting is to spray it with water the moment it bites.
Try finding out the reason why the cat is biting. Cats bite when they are fearful or frustrated. They also bite affectionately bite a person they like. Kittens usually bite out of playfulness, or when they are teething. Most of the time it's easy to tell why the cat is biting (eg, if the cat lays back it's ears, it's biting out of fear, if it runs after you/pounces on you, it's probably just playfulness) .Once you have found out why the cat is biting, you should work on stopping him.