Sit in padmasana or sukhasana(any comfortable pose), adopt nasika mudra.
Keep your spine straight and take few deep breathes to make your mind focused and relaxed, bring focus inwards on your breathing.
Gently press jaws and open your lips as much you can comfortably, so your teeth are exposed to the air.
Inhale slowly through the gas in the teeth and focus on the hissing sound of the breath.
Close the mouth and slowly exhale through the nose
While doing this practice, focus on your breathings and feel the positive energy inwards.
Continue the same process for few more times or as much as you can according to your capacity and prefrences.
Maintain silence for few minutes, focus on your breathings and observe the benefits of surya anulom vilom.
Cautions and Limitations
Those suffering from heart ailments should not attempt retention of breath.
Under no circumstance should the breath be forced. Never breathe through the mouth.
Proceed carefully and only under expert guidance. At the slightest sign of discomfort, reduce the duration of inhalation/ exhalation/retention and, if necessary, discontinue the practice.
Pranayama should never be rushed.
Person with breathing ailments must consult the suitability of pranayama with their doctor.
Contraindications
As for sheetali pranayama. Practitioners with sensitive teeth, missing teeth or dentures should practise sheetali pranayama instead.
General Benefits
Reduces the amount of bile waste that causes heartburn.
Reduces high blood pressure.
Helps to cure mental problems like Depression, Anxiety etc.
Controls the hunger and quenches the thirst.
Calms up and increases the concentration.
As for sheetali pranayama with the additional advantage that it keeps the teeth and gums healthy.