I would say I do it similar to a lot of others here.
I do enough groundwork so that they're calm and accepting and have a bit of control. I introduce the bit to them on the ground, and drive them a little too.
I get on slowly but within the first ride, and want to make sure they're ok with me petting and bumping and touching them all over.
By the second ride usually, we're outside the pen (depending on the horse), I like to be trotting by the third or fourth. I don't wait too long to canter, usually a few rides after the first trot, but I want to know I have control and steering at the trot before I take them faster. I always use another horse when introducing the trot and canter to young ones - it's just easier to get them going the first time. I just don't make a habit of it, and after (and during) the first trotting or cantering lesson with another horse, I usually expect them to be able to move off by themselves.
Anything after this is based on the horse. I am to be out of a pen/arena entirely, on the trail or at least in the open by the fourth or fifth ride, but as smrobs said, you don't want to push them farther than they can handle. They do need pushed, and they do really need to be RODE more than other horses, and the more you ride them like they're broke, the faster they're going to get broke.
Last edited by Paradise; 08-15-2012 at 10:12 AM.