Paper artifacts, made with the same care as the writing.
Right now
The Physiological Sigh
Two short breaths in through the nose. One long breath out through the mouth. Repeat three times.
Anxiety first-aid card
What to do right now.
Six techniques on two sides of a card. Three for the moment you're in, three for building a calmer baseline. Print it, keep it somewhere you'll find it at 3am.