Knowing how to ride a square halt is very important, not only to gain marks, but it is also the first and last impression the judge will get of the horse in a test.
The horse must halt straight, square and maintain his outline.
Firstly take your horse in hand with a schooling whip. Walk the horse forwards along one side of the school and then ask for the halt. If it isn’t square, touch the leg which isn’t square with the whip — you are looking for your horse to react by moving that leg forwards — ultimately a half step to bring the leg into a square halt. Repeat this exercise.
Next, mounted on your horse ask for several halts, ideally using a mirror so that you don’t have to look down at their legs every time you halt.
If your horse isn’t square, ask with your leg for the half step forwards. Remember to praise your horse with each forward step they take into the halt, even if it doesn’t end up square. Also remember to maintain the halt each time so that your horse understands immobility.
If the horse is strung out and not engaged then your halts are more likely not to be square. If your horse is engaged then it is more likely to correct itself going into the halt than once the halt has already begun.
It’s also a good idea to practice taking your hand off the rein as though you are saluting, and then replacing your hand so that the horse learns to stand still throughout this movement.
You must get a reaction when moving off from the halt and try to avoid doing all of your halts in the same place so that your horse doesn’t anticipate the movement.