1 trick that seemed to work for us was we hung bells from the door handle and we swatted the bells with his paw each time we took him out for potty time. Pretty soon he would jingle the bells and we would take him out. The key is to take him out every time he rings the bells even if you just took him out. That got a bit annoying but it paid off in a week or 2. Now he jingles bells & out he goes for potty. I made my bells by stringing yarn thru cheap bells from the craft section of Walmart, then tied to door knob. Just an idea.