Simple visuals make a difference, but @barbarah19, I've seen them backfire if used too soon. People get stuck on the picture instead of listening to the rules. Do you adjust when you bring out the marker based on how fast folks are catching on?

I mean, my friend lost a whole project file when an auto-update messed with his software. Just saying, sometimes that hassle finds you anyway.

Honestly it's wild how such a tiny fix can save an entire instrument. Reminds me of my old clarinet that had a similar hairline thing, @hannahgonzalez, but in the wood. A dab of special glue did the trick and it's still solid years later. It really does feel like you beat the clock when you stop a crack like that. Makes you appreciate the little fixes that have a huge impact.

Talk to your friend honestly and explain you just liked her system. I've been there, and now I ask before copying big ideas, but small things like color codes are usually fine. For personal use, I don't credit every time, but if I share online, I tag the source. Most people get that inspiration is part of the hobby, so just be open about it.