Sithali

1. Curl your tongue as in the illustration below:
   
2. Inhale through your tongue, keeping it curled.
3. Close your mouth and hold your breath for a count of 5-10 [whichever is comfortable].
4. Then, exhale slowly through your nose.

The above constitutes one round.

Reverse Sithali from Azazel

1. Inhale through your nose.
2. With your mouth closed, hold your breath for a count of 5-10 [whichever is comfortable; the hold is optional].
3. Curl your tongue as in the illustration above.
4. Then, exhale through your mouth with your tongue curled.

The above constitutes one round.