Aum is a sacred sound. It calms the nervous system and ststrengthens the breath. It is also a way to attain Yoga.
God is the teacher of all teachers through time.
Sutra 1-26
God becomes present in the sacred sound of Aum.
Sutra 1-27
This is the purpose of repeating the sacred sound.
Sutra 1-28
"The sound of Aum allows the yoga practitioner to tune into universal vibrations."
Preparation
Find a comfortable seated position that does not stress the joints. This will allow the body to remain stable without pain and discomfort, a major distraction in meditation.
Exhale all of the air from the lungs. (Leave a little air in the lungs, the karma is smooth on the inhalation.)
Inhale into the belly so that the air meets little resistance. (The air collides with the earth in the ribs and thoracic region quickly on inhalation. Allow diaphramic breathing to occur sending air to the lower part of the lungs early in the inhalation.)
There is an old yoga breathing technique called Bhramari. This is done by exhaling the air while making the sound of a humming bee. This is also a good way to tune into the oneness of Yoga.