It does depend on the look you're going for and what colour you are applying. Like with a permanant french, some people although like the white don't always like it so bright so i would put pink over the top.
If you are using a darker colour then clear would probably be the answer. But then i've seen nails where someone has done a red tip and then put a clear with a glitter powder over the whole nail for a real glitsy look. just experiment is the answer, and have a good play.:biggrin: