Lead change!

You were probably looking at my horse Levi (my hunter), My horse Zorro (my jumper) is the one with the problem and the video I put up of Zorro he got every lead in the video (lol I guess I got lucky that day huh?)
Im going to ride tomorrow so I am going to try everything everyone has said.
Thank you everyone your being GREAT help :)

Doing figure eights around the ring will help. For example start going on the left lead then come to the center of the ring and right as you reach the center pull up hard on the right rein and kick with your left leg, this should switch your horse into a right lead canter. And continuously do figure eights around the ring switching your leads directly in the center of the figure eight by either lifting up hard with your left or right rein and kicking with your outside leg, eventually your horse will do lead changes on his own with this technique.

I don't really know if this would be the best way. Pulling hard on the reins may cause your horse to want to slow down and forward motion is very important when it comes to leadchanges. You also do not want your horse to change leads every time you go into the center of the ring. You should be able to have a set cue to signal lead changes, not just have your horse automaticly do a change in the center of the ring.

Your not pulling back on the reins your pulling up to get their head up in the air and kick with your outside leg I do this with my thoroughbred..and you also do it when you are coming off of a jump..and let me tell you it is a whole lot easier when your horse has lead changes automatically you don't have to work your butt off

I don't jump or anything I show AQHA but pulling there head up seems to me like it would hallow out there back and make it more difficult for them to do the change. There back needs to be up for them to do a nice change. When I am doing either horsemanship or equitation patterns it is very important that your horse is not going to do a lead change when you do not want them to because you will be disqualified. My horse is taught to respond to my cue, this is so he will change in the exact place I want him to which is something he needs to do in a pattern wether it be horsemanship, equitation, or western riding.

I would ysay do loads of counter bending and serpentines in trot, and really supple zorro up. Try to work out his stiff side, every horse has one. Simple changes should really help too. Don't do too much asking for his chnages in one session because it may stress him out at first.

Have your trainer or a friend watch you one the ground on your good sidefirst, then your bad and get them to tell you if they can see you doing something differently with your body/seat/hands/legs etc

My trainer always says inside rein out side leg. (We don't pull hard be just use are hand to ask nicely). But it hasnt worked. Im going to try the stuff you all have told me about.
Thank you everyone :)

Inside rein and outside leg does work well for getting the horses body in position for the change.

Yea that's what I do.