Life is complex. How do you make sense of it?
I grew up Catholic, so the initial answer was "Live like Jesus". Of course, it's not rational. But taking off the table a weak answer, doesn't automatically give you a good one.
I found a better one after reading The Virtue of Selfishness by Ayn Rand. The main concept is that to be moral and happy first of all you have to be Selfish.
I don't pretend to have a complete understanding of life. That's why I write these Public notes.