Start as if she were a puppy and take her out ,say every 20 min or so.Adjust the time to fit the need,if 20 min is too long to wait take her out every 10-15 min. Just pretend she has no training at all. When you put her leash on to take her out say something like,"Do you have to go out"? I've always used,"Do you have to go potty"? Yeah, it is a pain in the butt but what choice do you have?