I came across an interesting post on Quora about breathing—in particular, box breathing. Here’s a summary:
It’s the technique that Navy SEALs use to remain calm and focused under the most stressful conditions.
Take a deep breath in through your nose (focus on breathing into your stomach rather than into your chest).
Now exhale completely, forcing all of the air out of your body.
Repeat 2 more times for a total of 3 breaths.
Breathe in deeply through your nose for 4 seconds. Then hold this breath for 4 more seconds.
Exhale for 4 seconds until the air is completely out of your lungs. Hold the exhale for an additional 4 seconds.
There is no step 3. There is no step 3!