One of the best ways to make life a bit brighter is to simply shine a little light on others - it always bounces back and makes your day better, too. Real Simple has a list of ways make the people who are working around you - from mail carriers to bus drivers to receptionists - have a day that's nicer and easier, thanks to you.
A few of my favorites (so easy to implement!) from their list:
For the pizza delivery person: Switch on an outside light to help them find your home and make the transaction at your door easier.
For the mail carrier: I've never thought about this in exactly this way before, but your carrier knows your name (duh!) so it would be nice to learn theirs - and use it - when you say hello.
For the wait staff: Be careful not to take the merchant copy by mistake when paying by card - according to Real Simple, if the waiter doesn't have the paper copy to prove the amount of your tip, they are out of luck.
Check out the full article at Real Simple: Simple Ways to Make Someone's Day