I'm fashion slow, so I just assumed I was the last actor to figure this out.
Being on a few gigs, I realized I may not be.
I often have to bring a bunch of my own wardrobe choices to auditions (obviously) or sets, so I try to make things easy for me.
For along time, a reversible belt has been one of those things. It's a black dress belt -- but wait! Swivel the buckle, flip the belt, and now it's a brown dress belt!
I'm being a bit flippant, but I do find stuff like this useful. It's one more thing I don't have to worry about, so I can focus on the bigger craft stuff.
And it goes along with shoes that work with jeans or slacks, etc. (and for things like industrials, I'll check to see if my shoes will even be seen, because I find bringing a bunch of shoe options is a pain for me).
I got advice early on in my career that part of the start-up cost of acting is investing in appropriate wardrobe. I run into actors who haven't received the same advice (or have chosen not to make the same investment, which may be valid for them), and they tend to stress a lot more than I do about the "bring some wardrobe options to the set" request.