Most people use this as an oracle. On any given day, they draw a card that asks "what can help me now?" Over time you learn which mantra is good for what, and if you practice, i.e. mantraize, over time the mantra you need will emerge from your subconscious, cutting through the subconscious dynamics and your "non-reactive" quality will gain ground. By this time the cards have fulfilled their mission. As all, mantras also have a vibratory frequency that corresponds to everything in the Universe. Joy or sorrow, opening or closing are vibratory frequencies in the mind. When we chant a mantra we are choosing to invoke the positive force contained in those particular syllables. Affect on prosperity, acceptance, intuition, or any other possible benefits inherent in mantras, simply by chanting them we are setting vibrations into motion that shall have an effect. (3HO) 
The cards have a KY mantra on each and based on your intuition you choose the one that you need in this moment. 
You may work on this aspect repeating it 11 times or during 40 days and surrender the effects of the naad.