i couldn't find a picture of this stretch on the web, but I'll try to describe it - it is a low back/hip stretch.

1. lie on your back, left leg bent, right leg flat. try to keep the flat of your back on the floor - that is, keep your pelvis tucked if you can.
2. put your right ankle on your left knee, like you are crossing your legs "man-style"
3. now, lift your left foot off the floor and bring your left knee towards your chest. if you need help with this, you can reach down and pull a little on your knee, or have a partner push gently on your foot.
4. relax into the stretch you should be feeling in your right hip. as you relax, try to bring your knee even closer.
5. once your knee is as close as it will get, gently rock your hips to the left to increase the stretch on the right hip - without letting your knee back down if you can. you can use your right hand to push your right knee towards the left if rocking your hips seems difficult or uncoordinated.
6. Repeat on the other side.