Several people have come up with a mnemonic for how to tighten a nut.
"Righty Tighty, Loosey lefty"
The only problem is: this pre-supposes two things, 1) it supposes a top-centric viewpoint & 2) is assumes you are looking at on the nut directly (as opposed to underneath wot you are looking at).

When I was helping at Stroud FM we had microphones mounted on angle-poise arms and had a knurled nut to set the rotation position. Many times I had to get pliers on the thing to undo it. Other times it was hard at the other end doing nothing. Despite my notice that said "This nut turns both ways, one is WRONG" and numerous e-mails to that effect.

Any other sayings that are really useful if everyone has the same mindset?