Two minutes of box breathing, once a day, for a week. That is the whole starting assignment. Here is what to actually do, what to expect in week one, and how to make the habit stick past day three.
Box breathing is four seconds in, four hold, four out, four hold. One cycle is sixteen seconds, four cycles is roughly a minute. Here is how to practice it, what the research actually shows, and when to use a different pattern instead.
Slow breathing shifts your nervous system in about a minute. Box for acute anxiety, 4-7-8 for sleep-onset, resonance for daily training. Three patterns ranked, with the research and the honest "when it doesn't work" you won't get from a wellness blog.