It depends! I decided that if I'm wearing brown, it needs to have texture or shine, or be in a print. Since my hair and skin are shades of brown, matte medium brown feels drab. I should probably stick to espresso and cognac shades and leave the mid tones alone TBH.
Camel is close to my skintone, but enough lighter that it works. It feels like a needed addition in winter to the black/cognac formula that I wear in summer. It kinda functions as my white.
My eyes are hazel- and olive and forest greens are a no brainer on me! When I wear forest green with black, I do feel the need to add warmth somewhere, like my camel coat though. Otherwise it's too much coolness.
I guess rust would be my lip color, similar to LaPed's version, which I wear a lot.