Alicia Chenaux of What The FUG? has created this brilliant little tutorial that utilises a good windlight setting, and an easy to use UI setting to help you get the perfect colour!  And I still maintain that once you get the right shade for your feet, they will look good under most standard windlight presets!  Go on, give it a try

She also has a little look at my Omnihud, incase you haven’t seen it yet