I go take a walk. Beach would be ideal, but nowadays even at the park or lastly at the mall. Anywhere relatively safe to just walk and listen to music. I find it improves my mood.

Eating good food and taking a shower after a rough day helps a lot too.

Prior to my health and endurance being absolutely wrecked in the past year, I used to run. Ran as hard as I could through the fields near where I lived until my legs would die, all in the chase for that runner's high; but when it did hit, it was good. Nowadays I can't run as much, so I'm still trying to find new outlets, one of which has been messing with my selfhosted setup, another being writing paragraphs on lemmy lol.

Also, certain video game soundtracks evoke feelings of catharsis and calm for me, so there's also that.