A drill you can do is once you are at address, hold the golf club away from you, and then take it back. You should then feel the proper position on how steep you should take the club back. An over the top move is primarily caused by taking the club back too flat, then trying to compensate and get back on plane by coming across the body. For those that do take it back too flat, this should almost feel like you are about to chop the golf ball, that means you are making the proper movements. Once you feel that proper position from doing the first drill a couple of times, then from the top, feel like the club handle is a large rope. Go ahead and just pull that rope downward. What it gets you to do is start moving the hands down instead of across the body, shallowing out the plane. I hope this helps! For more tips feel free to follow my instagram @brandoncaiolagolf.