The other night we had a little ceremony before chanting, and we were all gifted with (tulsi) mala beads that had been blessed in Rishikesh. When you are chanting mantra with a mala it is called JAPA. Japa is turning your concentration to god. You're raising a low vibration to a higher vibration. Chanting mantra has the power to pull something in to you, or repel something away from you. There are mantras for protection ("Om Dum Durgayei Namaha"), to transform anger ("Shante Prashante Sarva Krodha Upasha Mani Swaha"), and to remove obstacles ("Aum Gung Ganapataye Namaha"). Also, mala beads come in all sorts of wood, seeds, and gems. There are certain types that correlate with certain deities and mantras, and really you should only ever chant one mantra on one mala. One Mantra = One Mala. Otherwise you confuse the energy of the beads. You want to infuse your beads with one prayer, one energy, one intention. A mala has 108 beads, so chanting one round would be saying the chant 108 times.
And as if that wasn't enough information for you, there is also a specific way to hold your mala beads. To begin, you use your Right hand. Keep the beads hanging between the ring finger and middle finger. Press your thumb against the ring finger to seal it in, turning your palm to face down. You use your middle finger to pull the mala in towards you, bead by bead, chant by chant. You never cross over the "mountain bead" (where the tassle is"), or use it to start or end. If you want to chant another round , remove the mala, turn it around, and begin again.
And so, let the Japa begin!