I've had Sam for a little more than three weeks, and in the beginning he would walk really quickly and try to break into a trot whenever he could. We've worked through the walking issue through circles and figures-8s, but the trot is still too quick for me. I get unbalanced doing small figure-8s at that speed, which I know is my fault because my balance should be better, but he does have a very fast trot, and I want to be able to slow him to a jog at times.
He's smart and willing — we've already worked through other issues on the ground and under saddle — but I'm not sure how to go about this trot thing. The circles aren't working (yet?), and half-halts don't do much. Any tips?