This breathing exercise comes from the Shaolin tradition and is taught early on in training as a way to gain mastery of the breath. It slows down the respiration rate and expands lung capacity over time. This is one of the most powerful breathing techniques for managing stress, increasing vagal tone, and improving athletic performance. There is no specific pattern other than inhaling and exhaling as slow as you can on your own. With practice you can slow the breath rate down to 1-2 cycles per minute.