To see if your bit fits your horse correctly, first check to see how low the bit hangs in the horse's mouth.

This should go without saying, but sometimes it's easy to overlook simple things. Look at the two corners of the horse's mouth and make sure the bridle is adjusted properly and the bit is hanging evenly on both sides. It shouldn't be higher on one side -- the two sides should be even.

Once the horse is properly bridled, look at the corners of his mouth. Is the bit creating one to three wrinkles? If so, that's good. This means the bit is adjusted as high and comfortably as it will go in the horse's mouth. As the old saying goes, the horse should smile, but shouldn't die laughing.

Next, open the horse's mouth by gently pushing the bars of his mouth (the area without teeth, by the corner of his lips). Be careful when you do this so the horse doesn't bite you or swing his head around and hit you.

You may not have much time to look in his mouth when he opens it, but try to see where the bit is sitting on the horse's tongue. The lowest point should sit at least half-way up the tongue.

With a bit that is jointed in the middle -- such as a jointed snaffle -- the joint will be the lowest area and should be no further down than half-way up the horse's tongue. With a straight bit that is not jointed -- such as a curb bit -- the bar itself should be at least half-way up the horse's tongue.

Preferably, the bit will actually sit a little above the middle of the horse's tongue, but the half-way mark is a good guideline -- see what seems comfortable to your horse.

It's extremely important that the bit does not hang too low. With a low-hanging bit, the horse is more likely to get his tongue over the bit. He will develop a habit of doing this, even if later the bit is properly adjusted. He will work his mouth and stick out his tongue, and this is a habit you don't want him to get into. While it may start out as the horse's innocent way of playing or adjusting to the bit, it will quickly become a habitual way of evading the bit and it's commands.

Horses initially being introduced to a bit for the first several times are very prone to getting their tongues over the bit, as they work their mouths and adjust to having a foreign object in their that they can't swallow or spit out. It can almost be expected that they will get their tongues over the bit at least once. So if you are introducing your horse to a bit, watch carefully for this to happen, and if it does, calmly rebridle the horse. He'll get over it eventually.

A low-hanging bit also minimizes the effectiveness of the bit. The bit slides around the horses mouth and pulls to the side when the rein is pulled, increasing the chance that the outside of the bit will actually be pulled into his mouth. A correctly fitted bit more easily stays in the same place, which means the amount of pressure and action needed to cue him is minimized