I know this is really strange that I thought of this when I looked at the question how do you get a dog to sit. Taking psychology this year really opened up my mind to the different ways we learn and percept everything around us. We recently went over the "learning" chapter. There is something called operant conditioning or what we call the rewards system. To get a dog to sit, it'd be like getting a kid to strive to solve a math problem. You give a reward for doing right. Show the dog (help rather) what to do. Whether it mean tapping it's behind to sit or having a trained dog do it in front of the untrained dog. Present the dog with a treat when he/she sits or does whatever trick you teach. Of course, it always helps to give treats for being on the right track. That will show the dog that when he/she does right, they get a treat. Thus, proving that operant conditioning works. With this method, you can teach pretty much anything. Well, nothing crazy of course. But like hand shake or jump or stand on hind legs. That would be a few good tricks to try using operant conditioning.