Japa is the practice of mantra repetition. Siddha Yoga students practice japa by repeating Om Namah Shivaya, the initiation mantra of the Siddha Yoga path. A string of beads called a mala may be used to aid concentration while repeating the mantra.
These malas were created to support Siddha Yoga students' practice of japa. Repeat the mantra, either silently or aloud, as you move each bead between your fingers, one bead per repetition. Mantra japa can be practiced anywhere and at any time.