What can I do to keep my horse from bolting out from under when I’m getting on him?
Thanks for the question. It sounds like you need to get this horse better desensitized. Can you put the saddle on your horse on both sides without your horse being tied and standing calmly? I would make sure I could do this before getting on him again.
Also teach your horse how to do Lateral Flexion, here is a link that talks about lateral flexion:
You will start doing this on the ground first. So start standing right next to your horse’s side with your toes going the same way your horse’s toes are going. Bend his head slowly toward you and if he moves his feet just move with him in your position keeping his head bent until he stops his feet.
Then release the lead or rein. Do this on both sides of your horse.
Then when you get him to where he will stand calmly without being tied to saddle on both sides, then I would start acting like I was going to mount up.
Go in small steps. Can you stand next to your horse and bounce up and down and have your horse stand calmly? If not get him to where you can. Start bouncing next to his side, if he gets scared and moves just keep bouncing calmly until he calms down then you can stop and pet him, then start over again.
Next start putting your foot in the stirrup and then take it out then put it back in. keep doing this until he is not at all afraid of it and is standing calmly.
Then with the horses head slightly bent toward you step in the stirrup and only mount up half way. Don’t swing your leg over your horse, if he can not just stand there then keep doing it over and over again until he can stand calmly.
Once you can bend his head laterally and mount half way with him standing still then go a head and mount half way up and then slowly swing your leg over, once on do your lateral flixion that you taught him to do on the ground over and over again until he will just stand still. If he tries to bolt off instead of trying to pull on 2 reins, bend his head laterally until he stops moving his feet and stands still.
Thanks for the question and I hope this helps.