Keep the inner heels and big toes touching as the legs draw up towards the ceiling as if being sucked through a straw. (yogajournal.com)
Once the seat is secured, take the right arm behind the back, bend the elbow and grab a hold of the right big toe / top of foot. (sonima.com)
From hands and knees, bring big toes together, separate knees wider than hips, and fold chest onto a block and rest your forehead on the floor. (mindbodygreen.com)