Bell training

It's when you hang a bell on your door and train your dog to ring it everytime he needs to go out. 

I taught my poodle to ring a bell when he has to go outside. Is this what you are referring to? It was quite easy. I hung a large jingle bell on rubber bands from the door knob. Every time I took Dugan out I would touch the bell with his paw or ring the bell  myself as we were going out. Eventually he got the idea. One night while we were watching T.V.  I heard the dinga dinga ling and there sat Dugan by the front door and the bell was still swinging! He usually paws at it or will use his nose to bump it which makes it ring too. It's really helpful except when he went through a period of ringing that darn bell every hour or less just to go out . He doesn't do that now, thank goodness.   

Cool< I guess I will have to hang one pretty low for Harley or he will have to stand on his hind legs to learn to ring to go potty.

We started using the bell when we got our gsd pup, and he picked it up in a matter of days!  It's so helpful because I dont have to keep worrying about when I have to take them out.  If they have to go, they'll ring the bell and I'll know that they have to go.

When we first started, I just grabbed his nose and bumped it into the bell while saying "Out".  I had to train him out of using his paw, because he'd leave scratch marks on the door. 

I train the pups to ring the bell for a treat, before I ever put in on the door. By holding the bell (handle or string) in my hand I can cheat a little if they don't get it and make it touch their nose, then click and treat. In a few minutes they are ringing the bell for the treat. Then I graduate to putting it on the door and click and treat for them ringing it. Once they have that down instead of the treat I let them go outside as the reward. I think this works faster than starting with the bell on the door. It's also easier for you since you don't have to run in and out 99 times to train them.
 
I do find as someone else said that when they first learn it they have you running outside all the time for no reason but they do seem to settle into the intended use after a while. The thing you have to committ to before you begin is letting them out every time they ring the bell, even if they are "lying".