To start the exercise, draw your right knee up toward your stomach, flex your foot and kick it out in front of you at waist level or lower, and then allow the foot to touch back behind your body.
Once you have that down, begin to lean into the move by leaning back when you kick and forward when you touch your foot back behind. This will engage your entire body.
To make it more challenging, as you lean forward, touch your hands down in front of you, paying attention that your front knee sits right on top of your foot and your body weight is in your thigh and glute - not your knee. This is key.
If you can't go all the way down, try doing the move near a table or stool to try half way. Push down into that front heel to stand, lean back and kick again.
Do as many as you can on one leg for a minute, and then try the other side to work your ankle stability, leg and glute muscles, while providing a balance challenge.