How to do Kapalbhati Pranayama?
Sit comfortably on ground or mat with your legs crossed (Padmasana or Sukhasana)
Place your hands on your knees and relax
Inhale deeply and exhale
While exhaling, take out all the air from your lungs and abdomen. Your abdomen contracts when you do this.
Now breathe by focusing just on exhaling. You will breathe in naturally, you need not focus on it.
Exhale with force making a hissing sound from a nose
With each exhalation of breath, your abdomen contracts
Keep exhaling forcefully like this for the count of 20. This makes one round
Initially do 1-2 rounds only
Gradually increase the rounds as per your comfort and convenience
Kapalbhati Pranayama has two major benefits. One, it detoxifies your lungs to purify your respiratory system and second, it reduces belly fat.