You can do this exercise in a well-fit halter or bridle. Teach your horse to walk with you and pay attention to the speed you are walking. Going left, take a lead rope or reins about 10-15 cm from the horse's head in your right hand and take the end of reins and a dressage whip in your left hand. Stand facing forward beside your horse's shoulder, slightly in front of it. Start walking. If your horse doesn't walk with you touch her with the whip. The way you are standing you will touch the side or may be flanks. Tap lightly until your horse makes a step. Stop tapping instantly your horse makes one step and start walking with her. Walk with your horse and pay very close attention that she is by your side with her shoulder slightly behind. She must keep the same pace as you. If she is slow, tap her with the whip. If she is fast close your right fingers on the lead rope or reins and slow down yourself, release and repeat a few times. If that doesn't help start making small circles. Your objective to keep yourself slightly in front of your horse's shoulder facing forward. If your horse outruns you, turning left will put you in a correct position. When you are in a good position try to walk forward again. Turn to small circles as many times as necessary until your horse calms down and walks with you. Do not work for long 5 minutes is enough. Work on the other side of your horse for 5 minutes too. Remember, when you are on the right side of your horse, you keep reins in the left hand and your whip in the right one. Have a lot of patience and attentiveness toward your horse. You must notice a smallest sign of obedience to stop asking. If you get angry it will cloud your mind and you will punish more and will not praise when it is necessary. It sounds easier then it is. When your horse starts walking by your side and keeping an eye on you start change your speed and observe your horse's reaction. The objective is the same, your horse must stay by your side. Use the same methods to speed up or slow her down as described above. However, be nice to your horse, do not try to catch her trying to be too fast or too slow suddenly. Work in progress depending on the results.