Although Hollywood and television often portray dogs with human thoughts, values and even words, it is important to remember that your dog is not a person. Dogs have different needs than humans do. One important element in a dog's life is his need for a pack hierarchy. Include all family members in setting these rules so that they know what is allowed and what is not.
Consistency is very important.
Everyone must follow the same set of rules. Teach your dog the rules by firmly but gently discipline him for breaking them, and lovingly praising proper behavior. The next thing you must do to assume leadership with your dog is take your dog to obedience school. You cannot control your dog if he doesn't know or won't obey basic obedience commands. Most areas offer puppy kindergarten classes which are set up for very young dogs whose attention span is short.