Expanding Box Breath
This is the most returned-to practice of all the sessions I've created with Othership.
It's an expanding box breath designed to improve your breathing and help you handle stress and anxiety in your everyday life.
Each round adds a second to every side of the box. As the box grows, you'll feel a rising urge to breathe. Relax as much as you can to stay with the discomfort. That's the training. Whenever it gets too much, take a couple of breaths to recover, then return when you're ready.
Practice when you're calm and collected, not when you're already feeling stressed or anxious, as that can make it worse. Do it once a day for a month and notice what changes for you.