Okay, this is literally straight from Clinton Anderson. I do go off this method and have found some things work better than others but for a general idea. Here's the link as well to the seven games. Again, you don't have to follow these word by word, they're just a GREAT starting point. Most of us here don't pick one trainer to follow we blend them all together.
Parelli Natural Horsemanship: The Seven Games
1. Begin by establishing your "hula hoop" of personal space. Step away from your horse and, with your stick, draw a circle all around you in the dirt. If your stick is about four feet long, by bending over and reaching with your arm, you should be able to create a space that extends about six feet out from you in every direction. Your horse must stay beyond this space, so that his nose is about seven feet away from you.
2. Here's another way to check that your horse is far enough back. Extend the stick toward his head; there should be about a foot of space from the end of the stick to his muzzle. This establishes where he should be at rest.
3. To teach your horse to maintain this distance, back him away whenever he moves in closer on his own. Do this by wiggling the lead rope and swinging the stick from side to side in front of you as you walk toward him. Do it as vigorously as needed to get him to step back, then stop and praise him, then continue. Your goal is for him to begin moving back with energy the instant your body language says, "Back off."
4. Alternate the above method (wiggle and wave) with "marching" to ask your horse to back up. In this method, carry your stick as if it were a ski pole, and use an exaggerated marching motion, working your bent arms up and down as you step forward. If, as you approach your horse's chest, he hasn't begun to move back, you can flick your wrist such that the stick taps him on the chest as the arm carrying the stick comes up.
5. If your horse gets mouthy as he tries to move into your space (common among young horses and stallions), recondition him by taking the fun out of it. Do this by "mouthing him back"--rub his muzzle vigorously with both hands for about 20 seconds, using enough pressure to be annoying.
6. Don't hurt him as you rub, but be firm enough to get him to step back, as my horse is here. Be like that uncle who used to scuff your head playfully when you were a kid; eventually you learned to avoid him. You want your horse to learn to keep his muzzle to himself.
7. Over time, your horse will learn to stand respectfully at a distance and await instructions, as my horse is here. Be like that uncle who used to scuff your head playfully when you were a kid; eventually you learned to avoid him. You want your horse to learn to keep his muzzle to himself.