The quickest and easiest advice I can give you for this is to get a foundation that matches your skin colour on your feet and just blend it properly when you apply it. Alternatively, you could also consider applying a good self-tan product, such as St Tropez which is a very natural looking tan. In the long-term, of course, if and when you get around to it, I would suggest trying to treat the problem. There are some really wonderful options for uneven pigmentation. But for a one nighter, I’d say get yourself a good foundation that matches the colour on your feet.