Ho to do Gorakshasana:

Bend your legs and join the soles of your feet. Place the joined heels under your genitals( at the place between your anus and penis or vagina). Make a grip of your hands like a comb and catch the front portion of your feet. Your both thumbs should take position on your toes. white keeping your spine straight, try to touch the ground with knees or should be as near the ground as possible. Fill your breath inside for some time. Stay in this position as long as possible with out exhaling. then return to the position of rest while exhaling slowly. Concentrate on swadhistana Chakra.

Second Position:

In the second stage, Sit on your heels and place your hands on your knees, Press your knees to the ground with your hands, keeping your waist and face straight. Stay in this position for some time, then go to the state of rest.

Benefits of Gorkashasana:

Seminal glands get good exercise by this asana. It transmutes the seminal energy, and is particularly useful  for those suffering from wet-dreams. It also cures the ailments of genito-urinary system.