How do I safely mark up my Sky Atlas 2000?

But, back to my point. At first I had thought that I wanted to draw
the constellations into my Star Atlas 2000 (I have the deluxe
laminated version (black on white)).. I now think that I'm going to
hold off on that for a bit, but I am wondering what would be a good
marker to temporarily write on the maps with (something that will
wash/rub off). Things like comets that I might want to mark on the
map for a few nights but then get rid of.

I know I could just experiment, and I probably will with any ideas you
give me, but I thought I'd ask if you have any suggestions/experience.

Mark

Dull black crayons or, failing that......lipstick.