Sitting in a comfortable position, begin to focus on you breath. Curling your tongue as in the picture. Slowly inhale as you bring our nose toward the ceiling. To exhale, close your mouth, exhale through your nose as you bring your chin back to neutral. Repeat breath 8 - 12 times.
Sitkari Pranayama is an alternate for those of use who do not have tongues that curl! To inhale, place tongue behind your bottom teeth, make a small opening in your lips and slowly inhale as you tilt your nose toward the ceiling. To exhale, close lips and exhale through nose while bringing chin back to neutral.
http://www.youtube.com/watch?v=4pwcRbKsFnE good youtube video