Theories as to fitting the snaffle vary between horse owners, but the most common theory of fitting the snaffle is to adjust it so that it creates one or two wrinkles in the lips at the corner of the horse's mouth. The best way to determine how high a snaffle should be is to begin with the bit just touching the corners of the horse's mouth, forming one wrinkle. If the rider holds the cheekpieces of the bridle and moves them up, there should remain enough give in the bridle to raise the bit in the horses mouth, however, there should not be excessive slack in the cheekpieces when this is done.