I recently got a QH gelding that was a eoper in his younger years, once he was done with that he went to a guy who taught him to do some reining moves, then he sat in the pasture for a couple years. Basically, I can tell he still knows what the moves are, but he is very rusty, any tips to help get him back into it? Thanks in advance!

Groundwork. Alot of the things (Stopping and backing) can all be done on the longe line. Practicing these things without you on his back will not only help him dust off his skills, but will improve him once you go to ride. He will be more responsive, balanced etc. Many good youtube videos show you some of the ground work. Look for ones that are by smaller trainers or are by people just using a longe line and voice commands. No need for training devices if you just are giving him a refresher.