I start all my colts in a halter,works kinda like a pencil bosal.Then i'll let them pack a snaffle around,and two rein them for a couple days,helps them get the feel of the snaffle without bumping on their mouth right away.All that time,i'll be asking for a couple steps of collection here and there to get them dropping thier nose and asking for vertical and lateral flexion.If you've done your ground work well,it's real simple once your ahorse back.And best of all,NO GIMMICKS!!Soon as they feel a little pressure from the reins they drop their nose and find a release of pressure,and you just build a few steps at a time,till you can pick up on them and get them to keep that collection as long as you need.Anything you need to get accomplished can be done without gimmicks if given enough time and patience!Although not everyone can take as long to get the horse going as others it pays off in the end horse.I don't use martingales,but some of my freinds do and they work for them,so use what your comfortable with,but it wont be the same after you take the gimmick off the horse.