The short version
Before any pressure moment: breath (chest or belly, fast or slow), jaw and shoulders (set or loose), belly (gripped or open), pace (rushing or not), and a number from 1 to 10 for how keyed-up you are right now. Run it before you decide anything else needs doing.
What the research says
Craft, not a trial. The chapter’s physiology (that anxiety tracks how you interpret sensations, not how sharply you detect them) rests on two large meta-analyses and a two-year study of four hundred young adults, cited in the Notes under Chapter 3.
Rooms where it does the work
Two rules, no exceptions
Never practice any technique on this site while you are driving, operating machinery, or doing anything that needs your full attention. The slow ones can make you drowsy, faster than you’d expect. And never practice a breath-hold, bellows breath, or any vigorous breathing in or near water. Read Before you begin for the doctor’s list and the rest.
The short version is a reminder, not a lesson. The chapter has the story, the steps, the mistakes, and the limits.