Most people have a set of principles that they try to live by, making decisions based on these self-imposed rules.
These can vary from person to person, and culture to culture, but there are generally some common themes like kindness and moderation.
For example, many folks try to live by what is often referred to as "The Golden Rule":
"Do unto others as you would have them do unto you."
Reddit user u/kingfish asked:
"What's the one rule you live your life by?"
Impact
Giphy
Try to make a small positive impact whenever you can. One nice gesture can go a long way for someone.
Golden Rule
The golden rule (treat others the way you wanted to be treated). I was very unfortunate in the family department. All I knew when I was younger was I never want to be like them but I have no idea how. Thanks for my schools for applying the golden rule. It helped me figure out a way to think the way I wanted to and hopefully be a decent person.
Giphy
Moderation
"Everything in moderation, including moderation" is honestly my favorite life motto.
Once you get it into your head, everything suddenly becomes easy.
Learn
Never stop learning.
Regardless of how trivial something may seem in the immediate, it will almost inevitably be useful sometime in the future.
80/20
Giphy
The 80/20 rule. Doing something very good (80% level) takes 20% of the effort, the final 20% (to get to perfect) takes 80% of the effort.
Stop trying to be perfect. Instead of sinking a ton of effort into doing a few things perfectly, go around doing bunch of things very good for 20% effort. People will think you're a god.
Also stated as "don't let perfect be the enemy of good".
Accept it
Accept who you are now while also continuing to be a better person than you were yesterday.
@bfgilme/Bluesky
@agent672/Bluesky 
@everyonel9vesmikey/Bluesky
@_oRyca_/X
@jointheunionus/Threads
@MarkRuffalo/X
@joannefirth/Bluesky
@F_Don8/X