Dog Jumping

when the dog jumps up, you are supposed to step on one of the rear feet and say "no" or "down".  keep doing it and the dog should learn.

Try to recognise situations where the dog is liable to jump on someone, and put your hand on him keeping him on the ground. When he calms down, praise him and he will learn that he gets the most reward for keeping all 4 feet on the ground. 

If you need a quick method for a big dog, one of the best methods is to bring up your knee so that as he jumps his chest hits your knee. this will cause the dog discomfort and teach him that jumping on people is not a good idea. But of course this has to be done by everybody, not only you (including your grandmother ).

yes this is exactly what you should do. tell everybody to put up their knee so it hits the dogs chest. and it wont cause the dog any serious pain, just remind him/her not to jump anymore.