Here’s a handy tip: we always keep a PanPastel lid handy to remove colors from the palette trays or to place the colors in the palette. As the tray cavity holds the colors securely, threading a lid on the pan of color makes it easier to grip it, and helps prevent your fingers from touching the other color surfaces.
So although the palette tray’s cover does the job of covering the colors once you have finished painting, try to keep at least one lid available for an easy way to remove and replace the colors in the palettes. (Each PanPastel set comes with at least one lid, and of course the individual colors are sold with a lid.) More info on the palette trays can be found here (including an intro. video): http://www.panpastel.com/