Smell is the one sense wired almost directly into the brain's emotion and memory circuits, which is why a smell can put you back in a place thirty years ago before you know what happened.
Paying attention to it as a mood tool is a neuroscientist's personal practice, not a studied one. It costs two seconds. Evidence: worth trying
Same theme: A lift
A lift
Green space, weekly
Once a week, somewhere with trees or water, for an hour or more. Walk, fish, bike, sit.
1 hour a weekEvidence: decent
A lift
One creative hour a week
Draw, play, build, cook something new, write. An hour, no goal, nothing to show anyone.
1 hour a weekEvidence: worth trying
A lift
One real win a day
Every day, finish one thing you can point at. A fixed hinge, a sent email, a run. Write it down at night.
no timeEvidence: worth trying