Gomukha-asana: Cow-face Posture
Steps:

1. Sit in a crossed-leg position, right leg over left.
2. Spread the legs as far apart as possible without bending the knees.
3. Bend the left knee and place the bottom of the left foot against the inner left thigh. Bring the left heel as close to the perineum as possible. Keep the left knee on the floor.
4. Grasp the right foot with the left hand and keeping the foot on the floor place the heel of the right foot against the front-left portion of the left buttock. The right knee should be directly on top of the left knee.
5. Inhale slowly through the nostrils and raise the right hand over the head and bend the right elbow. Reach behind the back with the left hand and clasp the fingers of both hands (forming an "s" shaped lock).
6. Hold the posture as long as you can comfortably hold the inhale breath.Exhale slowly and then repeat the posture reversing the arms and legs.

Instead of holding the posture while the breath is held, you can try holding the posture while breathing gently through the nostrils. If you choose to breath then hold the posture for thirty seconds to a minute. Repeat the gomukha-asana two to three times on each side.
If you are unable to lock the fingers behind the back you may grasp one end of a small piece of cloth in the right hand and the other end of the cloth in the left hand.

This posture stretches the arms, upper back, chest and the sides of the chest and abdomen. As the shoulder blades are stretched backward the lungs are expanded and as the abdominal muscles are lifted the stomach is toned. It helps to relieve neck strain, backache and tight shoulders. The hands, fingers and wrists are strengthened.