It’s like 3 pull 9 kick freestyle except it’s 1 pull 9 kick backstroke. Take a deliberate straight arm recovery stroke. The thumb comes out first, elbow straight, wrist twists so pinky faces down as arm enters the water roughly in line with your shoulder. Now keep that arm extended in the water and kick about 9 times rolled 45 to 60 degrees on your side. The other arm (at your side) is in the position ready to take the next stroke. By taking a break between each stroke to perform 9 kicks you’ll not only get to practice kicking on your side, you’ll also have time to think about how you’ll perform the next arm recovery correctly.