were calling this "begging" rather that "sitting up" to avoid the confusion with the obedience command "sit" for this the cue can be "beg" or "up"! choose one and stick to it. give the dog the command and then show him what you want to do and show him how to do it. if the pup has a hard time balancing use a corner in the room to start out. when he does it reward and praise him do not however let him work without the supporting walls till he has learned how to balance himself well. Repeat several times a day for a few minutes each session.