Amrita Nada Upanishad describes OM Meditation. The steps by step method is:
- Select a place free from disturbances. Spread a mat made up of Darbha or Kusa grass.
- Keep the mind free from any disturbances
- Facing north, assume any yoga posture among Padmasana, Swastikasana, Bhadrasana or any other posture which can be practised at ease.
- Mentally mutter ‘Om’
- Close a nostril with one finger, inspire through another nostril and retain the breath to maintain Agni (fire) at Muladhara. Contemplate on the sound Om only.
One should practice this Om Meditation for many times to get rid of the impurities. One should perform this meditation traversing from Gross state to subtle state, beginning with navel and upwards.
One should practice this Yoga with closed sight and with the firm foot without a tremor. The union is stated by remaining without a tremor in the hollow stalk (viz., Susumna) alone is Dharana. It is reckoned as 12 Matras in point of time or 48 seconds approximately.
The subtler state of Om never decays. For the reason, it has neither soft consonant, nor consonant, nor vowel, nor palatal, nor guttural, nor labial, nor nasal, nor the semi-vowels, nor the sibilants. Prana travels through the path through which Om goes. In other words, wherever the Pranava goes, Prana follows. Hence the constant practice of this technique is needed.
Then the Upanishad mentions the impediments that the Yogi normally encounters with. The yogi should avoid fear, anger, and sloth. He should not be too vigil or slumber. Likewise, he should not eat too much of food or fasting. These are seven impediments to yoga.
The yogi who practices Om Meditation daily like this, attains the wisdom of Self in three months, sees Devas or Gods in four months, becomes Brahma Nista in five months and gets enlightened in six months without any doubt.