This is a safe and effective way to teach or reteach your horse to load safely on a trailer without causing injury to you or your horse. The first thing to remember is to stay consistent with the cues you use with your horse. They can be voice commands, hand, or body cues. This program can be completed in an afternoon or over a month. Work at a pace that is comfortable to you and the horse. You will need a snaffle bit attached to the halter, a lunge line, and a dressage whip. NO TREATS.
Step One is to teach the horse to step forward on your command. Do this by holding the lunge line a couple of inches from the halter and lightly tapping him on his left hip. Use your cue. This could be saying walk, clucking, leaning your body forward, or a small tug on the rope. As soon as the horse steps forward stop and pet him. Repeat until he is moving forward with your cue without the whip touch on the hip. Lots of petting and voice rewards. Extend this exercise by lengthening the time that he walks before stopping him.
Step two is to start toward the trailer. Walk as close as he will allow you to get. When he stops stop with him. Just stand there and pet him as long as he wants to stand- 15 minutes to hours. When he's ready to move forward go again. When he stops stop again and repeat the standing and petting.
Step three is reaching the actual trailer. Your horse is standing at the trailer. Keep his nose pointed toward the trailer. You are standing beside him. Not in the trailer. Give him the same cue for walking forward you taught him earlier. Ask him to move forward touch him on the hip with the whip each time a little harder until he attempts to move, even if he just shifts his weight forward pet him. Then start asking for a foot. One foot on then back him off. Ask him to put his foot back on then off again. Do this 50-100 times. Then ask for then second foot. Same process. One on, same cue for the second foot, a little encouragement with the whip if needed. Remember when he responds lots of petting! When two feet are on back off the trailer. Same as the one foot, on and off repeat 50 -100 times. Now for the hind feet. Using the same cue both front feet are on the trailer, the back feet will be pushing the front feet further into the trailer. When the back foot comes on pet him and back off. See the pattern? When you finally have all four feet on the trailer back off slowly. Then on again. Always keeping the cue to move forward the same.i.e. a cluck and a tap with the whip. The pressure of the whip getting stronger until he moves then lots of petting.
Backing off needs to be as controlled as loading. Practice standing in the trailer, then asking him to backup. After a couple of steps stop and stand. Let him stand with his back feet out and front in. This is in case you need to stop him in mid departure.
The idea is to be consistent. Lots of petting rewards and patience. You can break this down into multiple lessons. It doesn't have to be done in an afternoon. Remember your horse needs to be comfortable working outside the trailer with your cues before you begin the actual trailer work. Happy trails.