One of the most powerful and simple pranayama methods (breathing practices) is Nadi Shodhana. It is designed to balance the right and left sides of the brain, thus bringing balance to the solar and lunar pathways of the metaphysical body. It also helps to purify all nadis or subtle pathways of the body, so vital life force can freely move throughout the body.
There are three major nadis, or pathways in the body, two running on either side of the spine in a spiraling motion, and the third in the center that follows the same pathway as the spinal cord. The left side represents the Ida Nadi is lunar, female, and cooling, while the right side is named Pingala Nadi and represents the solar, male and heating energy. When these two forces of the sun and moon within the body are harmonized it allows the prana, or life force energy to more easily enter the central channel know as Sushumna Nadi. The Kundalini Shakti, the serpant like spiritual force, moves along this pathway form the Muladhara chakra at the base of the spine, to the crown of the head, Sahasrara chakra.
Practicing this technique is easy, but it should be done with enthusiasm and concentration. If the mind wanders while performing it, gently redirect your attention back to the practice. Below is a simple hand gesture called Vishnu Mudra that can be used to help block the nostrils while preforming this practice.
Instructions of Nadi Shodhana
Gently exhale all air, block the right nostril with the thumb of the right hand, and then inhale a full three-part breath through the left nostril. Block the left nostril with the ring finger while simultaneously releasing the thumb and exhaling though the right nostril. Once the exhalation is complete, inhale through the right nostril, block it with the thumb and exhale out the left nostril. This equals one round. Do 6 to 12 rounds slowly. More rounds can be done if desired, but quality is better than quantity when it comes to pranayama.