Anulom Vilom Pranayam:

Procedure: Hold your right nasal with thumb, breathe in from left. Now open right nasal and close left nasal with middle and ring finger and breathe out from right nasal. Now breathe in from right nasal. Now close right nasal and open left and breathe out and in from left nasal so on.
Detailed Procedure:
Prana breathed in through left nostril represents energy of the moon, which symbolizes peace, and has a cooling effect. Hence for purification of Nadis, beginning of this Pranayama has to be made by the left nostril. Close the right side nostril with the right hand thumb. Inhale slowly through the left nostril till the lungs are filled. Then close the left nostril with the second and third fingers. Open the right nostril and exhale through it. Repeat this exercise slowly in the beginning, and with practice, increase the speed. When you are able to practice this exercise for a long time, inhale with as much force as is possible for you, then exhale also forcefully. This practice of inhalation and exhalation alternatively through the right and left nostril, as indicated above with force, should be done for 3 minutes. If you feel tired, rest for sometimes and resume. Regular practice will enable you to do this Pranayama for 10 minutes. After some practice being established, this Pranayama should be done for 5 to 10 minutes daily, depending upon one’s capacity. However, in summer season it should be done for duration starting from 3 minutes and up to a maximum of 5 minutes. If you practice this Pranayama for five minutes regularly on a daily basis, the coiled energy called Kundalini Shakti lying in the Muladhar Chakra begins to awaken. This is known as Kundalini Jagran.. While doing this Pranayama, mentally repeat the mantra “OM” so the mind becomes fit for meditation.
Duration: at least 10 mins.
Benefits:
• Regular practice of this Pranayama has the capacity of cleansing all your innumerable Nadis, which makes the body healthy lustrous and strong.
• Blockages in the arteries of the heart are removed and the arteries become clean, making the circulation unimpeded. If this Pranayama is practiced for 3 or 4 months regularly, 30 to 40% of blockages in the arteries are dissolved and removed, preventing the phenomenon of heart attack.
• Pathogenic cholesterol, triglycerides, H.D.L. and L.D.L. also get controlled, making the arterial channels clear for effective and unimpeded flow of blood in the heart.
• Negative thinking is replaced by positive approach to life. It increases enthusiasm and spirit, the Sadhak becomes fearless and feels blissful.
Special Notes:
• Breathe into lungs not to stomach. No organ in stomach absorbs oxygen.
• Do not hurry. Do it slowly.
• Rest whenever needed (in any pranayam).