The Martingale collar is an essential tool for many dog owners and trainers. Proper fitting of a martingale collar is needed to prevent your dog from slipping out of the collar and possibly injuring himself. Slip the martingale collar over the hound’s neck. Pull it up to the narrowest part of the neck, which is right behind the dog’s ears. Pull up on the smaller control loop where the D-ring is attached. The two metal slides should come together but not touch each other. If they do, the collar is too loose and needs to be adjusted. There should be a two finger distance between the two slides. When properly adjusted, it will ensure that the collar will tighten properly when pulled. Since all collars present the possibility of choking, you should never tie up your dog outside while wearing a martingale style collar.