From a standing position with feet separated hip width apart or slightly wider bend the knees and bring the arms behind the legs. Plant the hands behind the feet.
Lower the butt to the floor, keeping the arms behind the legs.
Slide the feet forward but without straightening the legs completely.
Bring the arms back, internally rotate the shoulders to free the elbow.
Reach the arms behind the back and bind the hands.
If possible, cross the feet in front of your head, right over left.
To exit, slowly lift the head and uncross the feet to make room for the arms to come forward.
Form tips
Proficiency in kurmasana is recommended before attempting this pose.
Keep bringing your shoulder under the knees before trying to reach back.
Support the spine in this position by engaging your core and back muscles.
Some practitioners find it easier to cross the feet first and then bind the hands.
Binding the hands first can lock the shoulders and torso into a position that restricts the natural range of motion needed for deep external hip rotation, making it harder to cross the feet.
If the bind is not accessible, you can use a towel or strap to connect the hands.
Risks
Reaching back to bind the hands can over-stretch the ligaments connecting the collarbone to the breastbone if the chest is not open enough. Don't force the bind, especially if the shoulders are not deep enough under the legs.
Tight hips and or hamstrings can cause intense flexion of the lumbar spine, and puts the practitioner at risk of disc herniation and muscle strains.