Some say air expulsion is more difficult than air intake at the beginning of the practice. It is because the swallowed air is apt all to go down into the stomach, and once air enters the stomach, it is difficult to bring it back from there. So it is important to detain air in the esophagus not letting it into the stomach, and then to move it back at once.
Practice, basic sound
1) When you have taken air into the esophagus, strain your abdomen at once relaxing the thorax, and the air in the esophagus will be brought back to the mouth.
2) Strain your esophageal mouth with your chin stuck a little, and increasing the abdominal pressure, produce the basic sound.
3) Then practice again and again until you can produce voice at your pleasure - taking in air, bringing it back at once, and producing the basic sound.
