How do you bell train your dog for potty time?

How do you teach your dog/puppy to ring a bell that I hang from the door nob when he needs to go potty?

Every time you take the dog out to go potty ring the bell or show him how he canring the bell after awhile he will make the association and start trying it himself keep doing this till he gets it

Funny you should ask this, my friend's dog is trained this way. She has the bell on the door and every single time the dog is taken out to potty, ring the bell, every time. She put a cord on it so eventually her dog grabs the cord and rings the bell to go out. Works great for her!