"It is best to do this meditation when you have time to sleep afterwards or when you have a hard day to face. Both times are best for this. It will give you absolutely powerful energy and will balance that most effective computer that we call the brain. It is the best remedy for 'brain drain.'"
Posture: Sit in Easy Pose with a straight spine. Interlock all of your fingers except your Sun (ring) fingers, which are pressed together pointing upward. The right thumb locks down the left thumb. Place the mudra at diaphragm level, several inches out from the body, with the Sun fingers pointing out at a sixty-degree angle. Close your eyes.
Breath/Mantra: Inhale deeply and chant Ong in long form, one recitation of Ong per exhalation (approximately 15 seconds, but in a group setting, each person chants in their own breath rhythm). The sound is created through the nose; the mouth is held slightly open, but no air comes out through the mouth. The sound comes from the nose by way of the back of the upper palate. Your upper palate will vibrate. Concentrate to do it correctly. Continue for 8 minutes.
"It may make you cough or sneeze or there may be pressure in the ears, but it will give you bright eyes, better ears, and good nose—your E-N-T will be perfect. It will affect the thyroid. It will vibrate your whole brain and do a lot of good things. All the hot air will come out through the nose. The mouth is open, but the sound comes out only through the nose.
"Ong is the sound of the Ajna chakra, the sixth center of consciousness. Vibrating the thalamus is a privilege. That's why 'Om, Om, Om,' there is no such thing 'Om.' There is, however, the sound of the Infinite which comes through the central nervous system (Shushmana) and touching the central nervous system. I have explained how to do it; it comes from the back of the nose but you have to keep the mouth open. It can go to any pitch. It requires practice but the practitioner enjoys it. It is very fruitful. It is so fruitful and so enjoyable that all you have to do is a maximum five times and by the third time you will be sitting like this… in bliss. Therefore it is very important, if you want to be in love with yourself, to practice this sound. That will give you a great essence and joy of life." –Yogi Bhajan
An even more effective variation of this kriya is to practice the same mudra and mantra in shoulder stand. The mudra doesn't touch the body and the chin is strongly locked to help balance the body. But use the support of a wall. You don't have to touch the wall if you are highly skilled, but be near the wall so that you don't fall over. Doing this kriya in shoulder stand creates the most powerful potent situation, but only do it in this manner after you have spent sufficient time practicing the kriya in Easy Pose.
©2006 The Teachings of Yogi Bhajan
Praana Praanee Praanayam p. 42-43