Well, we made it easier on ourselves by not allowing it from the start. That said, our boy is very, what I call, "paw oriented." He uses his front paws a lot and expresses himself with them. You see it when he plays with other dogs, and when he is in working mode and – oh yeah – when he's excited to see a person.
So: Your Dobe needs to know the meaning of your "no" command (whatever word or noise you use.) They need to respect "no" and have practice obeying it. That's a big part of the foundation. Beyond that, I am not afraid to put up a knee and catch them in the chest as they jump up at you. Unfortunately, I have not found any other person that is willing to do that, so it's harder to keep him from jumping on others.
Further, I have a command that is "do not put your paws on me." He learned what it means and he respects it 95% of the time. When he is excited and I can tell he wants to swipe at me, I issue that firm command. He has learned I mean it. Incidentally, I use the same type of command to get him to not put his teeth on me.
Boy, when the mailman comes to our front door my Dobe goes ballistic and part of it is really wanting to rapid-fire claw the windows that are on either side of our front door, and the window frames around them. I have to be very firm with him on that. If he does claw after I have commanded him not to, I go to him, grab his leg firmly and utter the command with great intensity. Then I grab his other leg and repeat. He, thank God, has slowly learned to almost never do it anymore. There would be little paint left if I didn't quash that habit.
Hope some of this was helpful.
I know a widely-used method is to turn around and ignore your dog if they go to jump on you. It doesn't have much effect on my little fireball, but it might on yours.
