You have to ride a horse Indian style: bareback, no saddle no blanket, no reins, just grab his main and say “Go! Baby!” in his ear. He will always slide move under you so you don’t fall off. He knows you let him run free. You will be one with the horse. Just grab his neck and lean into the wind. Been doing it since I was 6 years old.
That’s how I learned to ride. I didn’t even have a saddle until I was old enough to buy my own. I rode this Appaloosa a lot bareback but not in wagon trains. I have been riding since I was a kid. I miss it. You learn your balance without a saddle.