Cold water actually works better for that.

Laminated diagrams are a good start, but you're right about the sleeves. My uncle labeled his whole basement workshop with those plastic ones, and they lasted through a flood. The real problem came when his cat chewed through half the wires anyway, labels and all. All that work just became a colorful snack. It taught me that sometimes the critters are the real weak point in any system.

Yeah, they're super sweet when ripe. You can sometimes find them at high-end coffee shops that get fresh shipments in season.