Neti’ exercise is intended for the purification of the nostrils. The nostrils must be kept always clean. Unclean nostrils will lead you to irregular breathing. Irregular breathing will make you sick.
Take a fine piece of thread about 12 inches long. There should not be any knot in the middle of the thread. It should not be too thin and weak. Insert one end of it into the right nostril and catch hold of the other end firmly. Make a forcible, continuous inhalation and pass it inside. Then slowly pull it out. Again in the same way pass it through the left nostril and take it out slowly. Do not injure your nostrils through violent pulling. After some practice, pass the thread through one nostril and take it out through the other. In the beginning you will begin to sneeze profusely when you insert the thread into the nose. This passes off after 3 or 4 attempts. This can be practised when you find that your nostril is blocked from cold. There is another easy method of cleaning the nostrils. Take some cold water in your hand or in a wide-mouthed cup. Draw the water slowly through the nose and expel it forcibly through the nose. There are many who can do this quite easily. After one or two attempts some persons may suffer from slight cold and cough when they begin to learn this. As soon as they are all right, again, they can practise. You have seen many who draw the smoke of a cigarette through the mouth and pass it by the nose quite easily. If cigarette users try, they can draw the smoke through one nostril and pass it out by the other nostril or by the mouth. In the same way water also can be passed quite easily. Drawing water and expelling it through the nose is known as ‘Seet-Krama’. If you draw water through the nose and expel it through the mouth, it is called ‘Vyut-Krama’. In Gheranda Samhita it is stated that this Neti Kriya purifies the skull and produces clairvoyance (Divya Drishti). Rhinitis and coryza are also cured thereby.