How I teach a horse or mule to obey me, without my using reins, in just one short trail ride.
Premise:

1. Horses and mules HATE pressure on their flanks and mouths.

2. They respond eagerly to painless alternatives, if offered.

I use enough leg pressure to get the horse moving forward.

I knot the reins together as though for neck reining (If the horse can only plough rein, I'll cheat and tug on a single rein at first, while still neck reining).

Whatever I want the horse to do, I act it out first. If I want to turn left, for instance, I'll lean that direction, while lightly laying the reins against the horse's neck, western reining style.

This throws the horse slightly off balance, and the leg pressure on his flank annoys him. I pull one rein only if I have to, at first.

If the horse makes the tiniest move toward the left to restore his balance, I immediately relieve all pressure and let him walk along in peace for a minute or two.

The same for slowing down or stopping. I act it out first; bracing as though for a stop, tipping backward or forward slightly to control the horse's speed.

In this case, a slight bump on the bit will correct any reluctance to slow down, and a touch of flank pressure will move him forward, if needed.

The horse quickly learns that if he keeps my weight directly over his center of balance, he will never have to feel pressure.

This also helps if I accidentally lose balance, as the horse will instinctively swerve to keep me upright.

After being offered an opportunity to avoid bit and flank pressure, usually within ten minutes the horses, even Grand Canyon rental mules, are moving rein-free.

If you are calm and consistent, by the end of a slightly longer ride, you should be able to wrap the horse around your leg just by leaning hard in that direction. It's startling how much equines want to avoid pressure.

When learning something new, a horse will often sigh or yawn when he understands what you want.

I jotted this down for a horse forum I inhabit on Facebook.