I try to do an activity that requires attention, both mentally and physically; for me that’s usually playing guitar, but it could also be cooking, organizing, some kind of craft, whatever. usually what’s keeping me stressed out is thinking about how stressed out I am, so if I can distract myself from that and force myself to think about something else, it breaks the feedback loop, and doing something physical gets some energy out. not sure if it works for everyone, but it often helps me