Bhagavad Gita 6.13समं कायशिरोग्रीवं धारयन्नचलं स्थिरः।संप्रेक्ष्य नासिकाग्रं स्वं दिशश्चानवलोकयन् ॥

The Lord describes here the pose or Asana and the Drishti (gaze) in this verse.You cannot practise meditation without a firm seat. If the body is unsteady, the mind will also become unsteady. There is an intimate connection between the body and the mind.You should not shake the body even a bit. You should attain mastery over the Asana (AsanaJaya) by daily practice. You should be as firm as a statue or a rock. If you keep the body, head and neck erect, the spinal cord also will be erect and the Kundalini will rise up steadily through the subtle nervechannel (Nadi) called the Sushumna. Sit in the lotus pose or the adept pose. This will help you in maintaining the nervous eilibrium and mental poise. You should steadily direct your gaze towards the tip of your nose. This is known as the Nasikagra Drishti. The other gaze is the Bhrumadhya Drishti or gazing between the two eyrows where the psychic centre known as the Ajna Chakra is situated. This is described in chapter V, verse 27. In Bhrumadhya Drishti direct the gaze towards the Ajna Chakra with closed eyes. If you practise this with open eyes, it may produce headache. Foreign particles or dust may fall into the eyes. There may be distraction of the mind also. Do not strain the eyes. Practise gently. When you practise concentration at the tip of the nose you will experience DivyaGandha (various aromas)