Horses must be relaxed in order for the rider to effectively communicate, and Myler bits -- created by Ron, Dale and Bob Myler -- were help resistant horses better accept the bit. This style of bit is designed to release points of pressure on the horse's mouth, allowing the rider to use different bits as the horse's training progresses.
Unhook the cheek pieces of your bridle.
Position the Myler bit so that the curve of the bit faces the back of the bridle. Close the cheek piece straps around the metal rings of the bit and latch each piece shut.
Hold the bridle up to your horse's face to estimate the proper adjustment of the cheek pieces. Adjust the cheek piece buckles based on your estimate.
Place the bridle on the horse's head and make the final adjustments to the cheek piece buckles. The bit should fit snugly into the corners of the horse's mouth, making one or two wrinkles in the skin behind the bit.
Buy a bit that is the proper width for the horse's mouth. There should be less than a quarter-inch of space between the side of the horse's mouth and the bit rings. If the bit is too wide, it will slide around in the horse's mouth. If it is too narrow, it will pinch the sides of the horse's mouth.