I have a 5 y/o ottb. I like to do a lot of circles, leg yielding, squares, and just really bending their bodies, making them supple, always change it up etc. I think if you have rhythm then it's easier for the horse to follow. Also legs off, but they're no longer forward small squeeze, and a small tap with a dressage whip if they dont listen to your leg. There should be an instant reaction to your leg. They need to learn when you say go they should go n
I've 5 horses between the ages of 3 and 6 at the moment. The best way I find to get youngsters as light off my leg as I want is to do lots of transitions up and down. However when I ask them to move off my leg I give a squeeze and a click If they don't respond or don't respond as quick as I would like I take my leg off completely for about 3 seconds squeeze, click again but I back it up with a flick of a stick as well this time. When they move off I take the leg of and give them loads of praise. I do this exercise till they are moving off of a slight squeeze. Once they are responding I ask them to move forward and really push from behind, ignoring their head. Once they are using their hind end they will naturally drop their head and work softly up into a contact. This will help them balance and in turn help with their rhythm. Sorry, a bit of a long winded reply but I hope it helps some.
Circling helps a ton!! Use your inside leg to push them over and they will soon get the hang. This will makes it easier to jump 👍🏽