And its collary: When someone shows you who they are, your job is to see.
Always read the subject before you post.
Somewhere, in a box in the basement, I have a book named The Official Rules. Many of the entries in this thread are in it. Lots aren’t, but should be.
Never believe anything you hear and only half of what you see.
The little skull and crossbones does not mean that swallowing this product will turn you into a pirate.
Don’t have sex (even protected sex) unless you’re prepared for the responsibility of being a parent.
Keep the sun out of your eyes and be yourself.
Can’t believe no one has posted this.
Always use sunscreen.
It’s scientifically proven.
Always assume you’ll make a mistake, and prepare accordingly.
I heard it was “Don’t stick your dick in the crazy”.
You women turn everything around to suit you 
Get up right now, shut down the Dope, and go do something.
[takes own advice…]
Save often, backup regularly.
Measure twice, cut once.
Beware of the Hun in the sun
Try to be kind to people, they are all involved in their own personal struggles.
So true.
Don’t sweat the small stuff and remember that it’s mostly small stuff.
Don’t stop a fan blade with your tongue.
Pain is mandatory; suffering is optional.
Never nitpick something light-hearted.
Controversial. The most liberating statement in the English language is “Fuck it.”