What I have always done to get my horses to stand quietly while trimming is to start on one foot and work all the way around them. Don't just concentrate on the bad one. I use a soft cotton rope that is about ten foot long. Tie one end of it in a bowline around the foot right above the hoof, not too tight, but tight enough it won't come off when you pull on it. Then on the front feet stand by the shoulder and ask them to pick the foot up by pulling on the rope and maybe pushing on their shoulder to take the pressure off the foot. Then hold the foot up, no matter what they do hold it up. Once they stand quietly then slowly lower the foot toward the ground. When the toe of the foot touches the ground slowly allow the rope around their ankle to relax. If they try to stand on the foot, or yank it away lift it back up and start over. Once you get them to stand with only the toe of the foot on the ground and no pressure on the rope only make them hold that stance for a few seconds, then reach down with your hand, pick the foot up slightly and place it on the ground with your hand. That way they know they're done. Slowly work up until they will stand that way longer and longer at a set, that way they learn not to lean (there's nothing to lean on) and that no matter what they do they just can't get that leg away since you have the rope on it. You may even have to have the rope on the leg for a few trimmings, but they'll learn. You do about the same thing on the back leg, stand behind the horse (far enough they can't kick you) and then gently tug until they pick the foot up. They'll probably fight, but just keep ahold and don't let them put it down. They'll settle down and slowly give the leg to you until it is in the correct postition to trim. Now slowly give it back, it should land on the ground in the position it would if they were resting it. Same as the front, don't let them stand on it, they need to rest the toe on the ground with no pressure on the rope. Once they relax then walk up, pick the foot up with your hand and place it on the ground. They will learn quickly what you want and it makes them so much more responsive to you. If that was too confusing, let me know and I'll try to simplify.