Sit in any comfortable posture like Sukhasana, Siddhasana or Vajrasana (see sketch).
Keep left hand on the left knee. Keep the body and head upright. Close the eyes and relax the body. With the right hand manipulate nostrils as required. Place the thumb on the right nostril and ring finger (one next to the little finger) on the left nostril; the mid and index fingers on the eyebrow center (i.e., between the eyebrows on the forehead). See sketch.