"Mantra is not the name of a god or goddess or of a person. It is not a holy word or part of a hymn. Mantra is not sacred, nor is it a tool for concentration. It is a vehicle for expansion of mind and liberation of energy."
HOW TO PRACTICE YOUR MANTRA
"The sounds which you receive and the sounds you make, create resonant waves in the depths and surface of the mind. These sound waves have various forms known as mandalas which go deep and hit the depths of the mind. If you take a pebble and throw it into a pool- circles, waves or ripples are generated. Deep freeze the whole pool immediately and then look at it- follow the ripples and find the point where the pebble hit the water.
The process of mantra is very similar. First of all fix your mind on the nose tip or one of the centers. This is very important, because when the eyeballs move, the rhythms of the brain are affected and shadows move- the level of consciousness does not become steady. For that reason the eyes have to be absolutely steady. In order to create steadiness, you have to find one center, the nose tip, close the eyes, and fix your mind there. That is point one. Secondly, the nose is directly connected with the perineum, which is the seat of the most important center in the body- mooladhara chakra. When you concentrate on the nose tip the impulses keep moving from the nose tip right down to the perineum.
After you have been concentrating on the nose tip, become aware of the breath, the natural breath which moves at the speed of fifteen rounds per minute. The breath has to be felt at the nose tip, flowing through both the nasal orifices. Then synchronize your mantra with the natural stream of the breath, either one mantra with inspiration and one with expiration, or more than one mantra with inspiration. That all depends upon the length of your mantra and on your personal choice."
(Article from Yoga Magazine online. Mantra- Vehicle for Self-Discovery)