The Supreme Lord said: Sitting on a level seat that is not too high or too low, keeping the body straight and erect yet comfortable, placing the two hands on one’s lap and focusing the eyes on the tip of one’s nose, one should purify the pathways of prāṇa by practicing the exercises of pūraka, kumbhaka and recaka. Having fully controlled the senses, then one should gradually alter the practice to recaka, pūraka, kumbhaka One should glace at the tip of the nose for keeping the mind steady. The yoga scriptures say antar lakṣyo’bahir dṛṣṭiḥ sthira-cittaḥ susaṁyataḥ: when the vision is directed inward the mind becomes steady and controlled. Viparyayeana means performing recaka, pūraka and then kumbhaka. [Note: One should first inhale, hold the breath and then exhale. After this one should practice exhaling, inhaling,and then holding the breath. This however amounts to the same thing. Perhaps the second method should be exhale, hold inhale.]