Didgeridoo Instructor  

Didgeridoo Instruction
Circular Breathing
Now comes the tricky part: relearning how to breathe.  If you can hold
air (or water) in your mouth and still breathe in and out through your
nose, you can circular breathe.  Circular breathing is the ability to blow
out through the mouth and breathe in through the nose at the same
time.  Not as tough as it sounds.  As you are droning, use your cheeks
like a reservoir and allow them to puff out and fill up with air.  Then
close off the back of your throat, and while continuing to push out that
last bit of air from your cheeks, refill your lungs through your nose,
then relax the back of your throat and keep the sound going!  It's a
little tricky at first, but once you figure out the mechanics of it and
smooth it all out, you'll be asking yourself why you ever thought it
was so hard!