Lying flat on your back, as you exhale, bring one knee up and grab it with your opposite hand, pulling the knee across your body toward the floor. The foot of your bent leg is near your other knee, making your legs look like the mouth of a crocodile.
Stretch out your free hand (in the opposite direction from where your knees are stretching) and look at that hand. Breathing deeply, relax into the pose, and stay there awhile. Return to flat. Repeat on other side.