My skin is dark and I have a light spot on one of my toes. It is smooth but light. Does anyone know what I can do to get it darken or what kind of cover up I can put on it that will stay.

I think it's the dead skin that causes that color difference.. Try those strong peeling stones (or another product with which you can remove the dead skin) over those areas softly while taking a hot bath so that you peel while your skin has softened.. But if the white layer of skin isn't that thick then this process might harm your feet that's why in that condition try buying a cream or vaseline and apply it everyday on your feet before you go to bed and then wear socks over them so that they are fully moisturized until the morning... hope it works