Question: My paso has a major problem with mounting. He spins away the second my foot touches the stirrup. The  history on this horse is he is  a rehabilitated abuse victim. He is wonderful in every respect but this. He was retrained to allow mounting from the right side and dismounting from the left as former owner had an artificial left knee. He was excellent and never moved during mounting for the year she owned him. She put him at a sale barn when she was trying to sell him. Over 40 people attempted to ride  this horse. It was there that the problem started. Occasionally I can pull the outside rein around the horn when he moves away to pull him back to me. Sometimes he will then stand still, but most of the time it doesn't stop  him.

I've backed him in punishment for a few steps if he wasn't still and this hasn't worked either. Sometimes I will mount from the other side simply because he will be still longer on that side. Once I'm mounted he does not move until cued, but the problem is just getting on him without someone holding him. 

What else can I try? I realize he probably endured a lot of toes in his side and much mouth pulling which is why I don't touch the reins unless I'm ready to move off. He really prefers that. 

I am not a trainer for other breeds than Icelandics, so I won't say much as the
sheer size of the bigger horses makes it more difficult to mount them if they
don't stand still, so maybe my usual answers wouldn't work.  What I do want to
give as a comment though, is that repetition is often the best solution if the
horse doesn't want to stand still.  Try to set up some situation where the
horse stands still (or relatively still), and then mount it several times.  You
might ask a helper to hold the horse, and mount it.  Then ask the helper
to move gradually away, and mount the horse again and again, always taking care
to mount it carefully, so it's not a very unpleasant experience for the horse.
You might even give the horse treats or something if it stands still.  Let the
horse sometime walk a bit if you feel it's starting to get impatient by you
mounting it repeatedly, but stop every once in a while and dismount and mount.
Do this until both of you are bored to death.  The horse will maybe not always
stand perfectly, but if you work very much on mounting for a few days, just
like if you were teaching the horse sidestepping or some other difficult
exercise, the horse improves in most cases, and even stops the fidgeting
totally.  Then you can start working on the mounting under different
circumstances (without helper, out on the trail etc.) until the horse stands
still, always.  This might take you half an hour, this might take you a month,
but if you don't work on it the horse will hardly stop.
As for how to reprimand the horse, I usually don't reprimand them.  They are
quicker to learn this through repetition or boredom.  You can maybe correct the
horse a bit through reins, with your body position, by letting it stand up to a
wall or something etc., but reprimanding the horse does not help it to get into
the mood of standing quietly and relaxed still.
If you just mount once every ride, this will always be something causing
excitement or stubbornness in the horse.  Boredom is usually the key to this ; )

Happy trails.
Lukka.