Make sure to hold onto something stable such as a barre and set up your Flexistretcher for a side extension.
Begin with the gesture leg bent out to the side.
Slowly straighten the leg feeling the femur(thigh bone) drop into the hip socket and externally rotating all while keeping the hip bones level. Maintain the desired height of the thigh as the knee is extended.
Return to the starting position bringing the knee closer to you and keeping the tension in the strap by not allowing the knee to drop in space. Repeat 10x each leg
When ready to progress, practice the same exercise standing on something unstable such as a disk or yoga block. This will add focus to maintain turnout on standing leg while increasing height of gesture leg.