ANXIETY REDUCTION BY ENTRAINED BREATHING AND EXTRA LONG EXHALE
It's well known and studied that controlling one's breathing can help change and control one's body response.
I recently found that if I slow down my breathing to 6 breaths per minute with emphasis on a slight extra exhale, then it relaxes me.
The extra long exhale part I call it DARTH VADER breathing, as explained here
https://www.7cups.com/forum/HealthyLiving_141/ExerciseandActivity_825/DARTHVADERBREATHINGTECHNIQUEImadeittofixmyshallowbreathingwhenstressed_231131/
The 6 breaths per minute part I got from scientific studies I found.
To time my breathing so 6 beats per minute, I created a breath-reminder-beeper bookmarklet app recently made as explained in the link down below.
I find to be a very relaxing breathing training tool. I think it also might create breath "entrainment", meaning the body synchronizes to the beeping frequency somewhat automatically over time.
Note: 6 breaths per minute might be too slow for many people. What works for me might not work for you. The above is not medical advice. It's just sharing ideas and experiences. Always consult with your professional healthcare providers before making any lifestyle changes.