Anyone got any foolproof ways of doing this? My two are ace at sitting nicely with a paw on my lap whilst I manicure their front paws but won't stand to let me trim the back ones if I lift their paws and hold them backwards and if I try to get them to lie down and let me do it they wiggle and instantly jump up. They are big dogs, so I can't just wrap them in a towel and have them on my lap like I used to with the Guinea pigs 