I always use the same general color, but in a darker shade, on my toes. A pedicure lasts longer than a manicure, so my fingernail color might change several times between pedicures.
I would use a beige shade on my fingers if my toes were red, (and I didn't want red fingernail polish) rather than a pink, although a VERY pale pink would probably be OK. I really don't notice, or care, what others are wearing, unless it's something really strange.
edited to add: it's the undertones that matter. If they both have blue undertones, or green, or yellow, etc they will coordinate. If not, they might "clash."
I have a friend who is a textile designer, and it's amazing to hear her describe colors. She can combine colors that I would think would clash, but they look lovely. It's all a matter of "seeing" the the different colors in a color. I'm afraid I don't have that gift, so I play it safe.
