Again, start with the dog on a leash and sitting by your left side.  Step forward and when the dog stands up to walk along with you, place your left hand under his belly and your right hand on his collar and praise.  I like to rub the dog's belly while praising and offering a treat.  Then say, "OK," or "Release," and walk the dog forward and start again. 

At first your dog will want to sit.  Simply continue to practice until he get the idea.  After your dog gets used to this, gradually remove your hand from underneath his belly and say, "Stay," as you place the palm of your right hand in front of his nose.  If he sits, moves sideways, or continues to walk forward, go back to doing it with your hand rubbing his belly. 

Remember this takes time and you will need to build the distance that you can walk away from him or around him gradually.

If you are planning to do obedience, the stand is an exercise your dog will need to master while a stranger (the judge) touches him.