When you take your dog out you don’t want him to be running muck in the street, you want to show him off for the perfect dog that he is! Dog obedience training can be achieved in a matter of weeks with the right attention, dedication and patience.
There are a lot of obedience classes available. So if you can't teach your dog by yourself there is plenty support at the class, there are also other dogs there. Not only are you training your dog you are socializing him to which of course is the next step after sit, stay and come.
Dogs are kind of like children to an extent, except with a lot of fur, they need to be taught right and wrong.
I always find that treats are a great method of dog obedience training; you award them with a special treat when they have done something you have asked them to. If they don’t respond they don’t get a treat.
There is no point shouting at your dog as he will only become scared of you and you don’t want that, you want to form a great relationship with him.