I have a problem with not staying down on my shots. Since I've adopted the snooker-style 4-point stroke, I know immediately when I'm jumping up or not aligned correctly by whether or not the cue is touching my chest. Earl advises a lot of people to hold their breath when pulling the trigger on a shot, and that seems to work for some people as well. As far as practicing your mental game.... it's similar to the physical side. There are no shortcuts, just hard work.
Try this. Get a four foot length of fishing line (twenty-five pound test worked for me) and tie each end to a large, say 14/0 fishing hook. Put the loop around your neck and lightly snag the hook onto your scrotum.
When you prematurely raise up on a shot the hook will set and you'll damn sure not be doing that shit again. :smile: