so as a whitebelt i know i don't have much room giving out advice, but this was given to me by my coaches basically to train knee on belly transitions and maintaining your balance you can use the following two methods knee on belly to knee on belly transition 1) use a basketball/soccerball and position so the curve of your foot (down by the ankle) is on the ball and post your hands out, then just lift your leg and replace the ankle with your other ankle, all while trying to keep your hips over the ball. i found it took me about 40 minutes to really get the hang of it. keeping balance 2) if you have access to a swiss ball (the big rubbery ball that people do situps off of at a gym) then use it (haven't found an alternative to it yet). Position the leg you want to be on your opponents body on the top of the ball, then post out with your other leg. and then basically just try to keep your balance. its challenging but again, after a little bit you get used to it. i'll take photos if my descriptions don't make sense. hopefully someone likes this. again i know i'm only a white but i'd thought i'd share something i find useful.