There are a couple reasons that a horse might not want you on his back. The horse may be afraid of being ridden or maybe he just doesn't like to be. In order to figure out how to mount a horse without problems or danger, you need to be able to determine if the horse is responding from fear or nervousness or if he just has a negative opinion of the process.
It?s impossible to relax and enjoy yourself when your horse is fretting and you're worried he may be ?uptight? the whole time: bolt, buck, whirl around, jig incessantly or hurry at all gaits, crowd other horses, or even rear. Equally important, you worry about your own safety. The fix?? Read this from The Trail Rider.