Bounce one stride bounce one stride
I like 9ft bounces to slow my guy down. Placing poles before and after fences are really helping him figure out when to take off and to slow down.
Canter pole before but if they are running into the jump you can pull them up as quick as you can after they land they will begin to anticipate being pulled up and slow down, you could also try trotting into the jump until they have relaxed and then canter x
I like a canter pole into a small, wide oxer with another canter pole after, all you have to do is keep the horse straight and they have to figure out their own speed/feet to get over the jump successfully