I was trying to figure that out too. Best I could figure, you’d start by putting the rear legs through both holes then sliding it up to right behind your front legs. Then do some kind of maneuver where you pull your front legs up to your body and try your best to stretch the pants a little bit to get your front legs into the top hole then down and out through the front leg holes, then finish sliding the top hole up into place? Idk I’ve now thought way too long about how a centaur would actually put pants on.