This exercise is great for improving your around the netplay. It is used majorly when receiving serve. As with the push, you must step in with your right leg (if right-handed) contacting early with the ball. Your forearm should be parallel to the table.
Though TTFit set out exercises for you to try, they are mostly there for inspiration - feel free to deviate and adjust to suit your game better. The most important this is that you give it your best... always.