I get my hair colored tomorrow, but that's probably not why you checked in. This is supposed to be a world building day... although hair color can be vitally important to the real world we build for ourselves. But, I digress.
As a paranormal romance author, I'll admit, hair color is something I often have to go back and double check as I'm crafting my novels. My beta readers are even warned to watch for it.
In short stories I usually keep pertinent details together without a cheat sheet,