This is my aide-memoir, I hope it helps.
Always make a mental note to regrease your bits when you see a nipple.
Never grease a dirty nipple.
Grease your nipples and bits before you take them for a romp and again when you've finished.
Never abuse your equipment, look after it and it will look after you.
If you can't remember greasing your equipment - do it NOW.
Rub any excess grease between your fingers, shiny, lumpy or gritty bits are all bad and indicative of future pain,take preventative measures NOW.
DO NOT MIX TYPES OF GREASE (If you mix clay based and lithium based greases the damn stuff dries out and turns into grinding paste).