Never eat anything bigger than your head, never shoot pool at a place called Pop's, never eat food at a place called Mom's, and never shoot pool with a guy named after a city or a state. (There are often other things added to that, Never sleep with a woman with more problems than you, never pet a burning dog, never play leapfrog with a unicorn, Never play cards with someone who knows better and you don't... Probably more.
I find as you move through life, rules become simpler..
Things like... Never waste a b*ner, come to mind..
Or
Never trust a fart.