In no particular order:
1. Tell a friend something about them you like or admire.
For example: Their kindness, reliability, willingness to try new things, resolve, confidence, dedication, ability to cheer you up, or that you simply enjoy their company.
2. Be friendly to anyone, everyone.
Friendliness spreads — a smile can help someone feel happier and in a better mood, and more inclined to be nice in turn to others. It’s humanizing and inclusive, and at bare minimum will probably make you feel good.
3. Offer help.
Hold a door open, pick up something someone dropped, broadly ask someone if you can help with anything. Even if a person declines, the act of making them the offer has positive value.
4. Let someone in ahead of you in traffic, or on public transit offer your seat to someone else.
5. Donate anything you’re not using and don’t need. You can give items to an organization like Goodwill, a local charity, or an online free-sharing group.
6. Take care of a chore around the house or office that you usually don’t, or haven’t lately.
7. Genuinely ask how someone is doing and be clear that you’re paying attention to their response.
8. Tell someone how they made a positive impact on your life.
9. Tell a silly joke!
Go with a standard: What did the pencil say to the other pencil? — You’re looking sharp!
Or you can try something a little less clean: What did one toilet say to the other? — You look a bit flushed!
10. Send photos or videos of baby mammals. Puppies and kittens tend to elicit happiness and moments of relief and reprieve from stress.