Setup and Key Actions
Begin lying on your back, and extend both legs up toward the ceiling. Point your feet, and flex your toes back toward you. Keep the inner edges of your big toes together, heels slightly separated. Hug your legs together, and lower them down to about 30 degrees from the floor (or as low as you can without arching your lower back and jutting your low ribs forward). Extend your arms forward. Curl your head and shoulder blades off of the floor and gaze toward your low belly. Draw your belly in, and round your back. Narrow your two front hip points toward each other to engage your deepest abdominal muscle (transversus abdominis) to prevent your hip flexors from taking over. Press your thigh into your hand and your hand into your thigh for stability to engage the more superficial abdominals. Be sure to repeat on the second side.
If your neck hurts or feels like it's working hard in this pose, place a hand behind your head for support. For a less challenging variation, bend one knee in toward you, and hold on to the back of your thigh with that same-side hand. Press your thigh into your hand and your hand into your thigh for stability.