Cat massage expert Maryjean Ballner, who rocketed to internet fame when Everything Is Terrible posted her how-to videos, was on Letterman last night, where she informed Dave and the world that we've been petting cats wrong all our lives.

Maryjean's Cat Massage Don'ts:

1. Touching too fast
2. Touching with your fingertips only (use full palm).
3. Taunting the cat with a high-pitched squeaky voice.

Remember the rules!

Cat Massage Lady Maryjean Ballner [Late Show with David Letterman]

Related: If There was Ever a Win-Win Situation, it's Cat Massage! [Everything is Terrible]