1) Place the band just below or above your knees.
2) Lie on your side propped up on your forearm.
3) Place your feet together, one on top of the other.
4) Bend your knees slightly.
5) Lift the top knee open, keeping the feet together.
6) Hold for a second at the top and then lower.
7) Do not let yourself rock or rotate back as you open that top leg up toward the ceiling.
8) Make sure to focus on just squeezing the glute to lift.
9) Repeat all reps on that side and switch to the other side.
10) Beginners may start without a band.
http://redefiningstrength.com/10-mini-band-butt-exercises/