So what can be done? First, and I am not being a smarty pants here, just breathe. Seriously deep breathing helps your nervous system switch gears from "flight or fight' mode to 'rest and digest' mode, which calms everything down. Three deep breaths anywhere and anytime can instantly help.
Meditation, yoga, tai chi, walking, spinning, knitting, having lunch, walking in nature, or a belly laugh with your friends, all positively affect one's well being. Find what works for you and make the time to do it!
If you are experiencing a lot of stress, the first step is to identify what stresses you out the most and strive to resolve it as best you can, one stressor at a time.