Is it see through?
cause if it is or it isnt you can do this either way
im a big fan of black lacey skirts so,,
you can take plain black fabric then sew it underneath the black lace. or any other color to make it more colorful. (but only if its a lacey see through type)
if not then you can take any color or design fabric and sew it at the edge underneath and nake it a short color ruffle underneath the skirt.
kinda like below but make it longer and the ruffle bottom part be a plain hot color or something?
i would think it would look cool!!!