First, teach the horse with groundwork to lope/canter on the 'kiss' cue.
Then hang a couple of flat little RUBBER pans from each side of the saddle (saddle horn if Western). Lope the horse in ground work with those. They're annoying but not terrifying. Good prep for carrying a rider at the lope, altho one hopes that one rides better than a pair of rubber pans.

Next, ride at the extended trot. Really push for a fast trot and then frequently cue the horse to stop and praise and reward him. The idea, get him used to becoming calm again immediately after becoming excited.

Then push for the lope from the extended trot. As soon as the horse begins to lope, cue for a stop and let him rest. Repeat several times. The idea is that you stop him before he can scare himself or become overexcited. He also learns not to fear the lope. If you got him loping then loped and loped and loped, he might learn to hate it because he'd get so out of breath.

Watch horse training video lessons online "Look sister, is any of this filtering through that little blue bonnet of yours" image
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