Even if it’s only for a minute, at midday take your shirt off and get some sun.
That (direct sunlight), putting a smile on your face, and brief victory poses throughout the day are the quickest fix things granting instant happiness.
Everyday get some direct sunlight, don’t burn, yet get as much as possible.
This is a plus to SoCal, the sun must be nearer to the earth, and it’s sunny year round.
However, even if where you are has/gets snow on the ground aka winter, take your shirt off, and let the rays hit your upper body.
Direct sunlight on your upper body, regardless of temperature, does good things.
I’m known to shovel snow shirtless.
-J