Hi, Arlo @equanimous,

Always, I breathe in (inhale) through my nose with my belly rising, and blow out through the my mouth which is around the tube . About an inch or so of the plastic tube is in my mouth as I blow out. Do not strain.

The AD app has excellent detailed instructions on how to use the app. I still read them when I need a refresher. Be sure to read them.

The link below is one of the best videos I've seen that demonstrates autogenic drainage. The link takes you to a page with several different clearance techniques. You'll need to choose the autogenic drainage video from the link. It's slightly different from AD app but the underlying principles are the same. Plus, it demonstrates with an actual person how to use the tube.

FYI - it took me a couple of months until I felt after a session that my lungs were clear.

It seems all very individual what works. Let me know if it helps you! Good Luck!
https://bronchiectasis.com.au/resources/airway-clearance-videos