I want to give you some suggestions that will help you better understand the mantra and how to use it.
A mantra is a sound, word, or phrase, often having no meaning whatsoever. Your mantra might be "Om," "I am," "So hum," "Om namah shivaya," or any number of different mantras that correspond to various teachers or traditions. For a detailed explanation of four useful mantras, visit my article here.
Your mantra is a tool, so let’s make sure it’s as sharp as possible.
The first important thing to understand is that mantras fall into two general categories, and one of the categories leads to the next. In other words, the two general categories of mantra present two distinct ways of using them. These are the two ways:
1. Japa mantra
The first category of mantra is japa mantra. Japa means repeating or remembering the mantra.
So in japa the mantra is mechanical. You repeat the mantra mechanically.
Initially, you have to insert your mantra mechanically by deliberately repeating it inside your mind. This is japa mantra. You may feel the need to repeat the mantra slowly, as if the mantra is moving through a viscous substance like honey, or you may feel the urge to repeat the mantra quickly, as if the mantra is moving through thin air. Either is fine. But the trick is to allow the mantra to come at its own speed.
2. Ajapa-japa mantra
The second category of mantra is ajapa-japa. Ajapa-japa means constant awareness of the mantra.
The letter ‘a’ in front of japa means without. Therefore, ajapa-japa is the repetition and remembrance of the mantra without the usual level of mental effort.
So in ajapa-japa the mantra is natural. The mantra naturally repeats itself.
Eventually, you simply have to listen for your mantra flowing naturally as it repeats itself inside your mind. This is ajapa-japa. You may feel that the mantra has begun to resonate like a song that has stuck inside your mind. This is also fine. But the trick at this point is to allow the mantra to lead you to soundless sound, or no sound, so that you experience silence.