Dodging tools from black paper/cardboard are easier to use if one side is white. You can identify the are youd dodge. I use adhesive labesl for making the black paper white.
Not to hijack the thread, but I just thought I'd mention that it's always a small shock when I start to dodge/burn an 8x10 contact print and realize that I'm looking in the wrong spot to judge my lines. It's a little harder to figure out, but not usually a problem. I keep thinking that I'm going to mark the edges of my printing frame for reference, but I've never actually done it.
Tom, on Point Pelee, Canada
Ansel Adams had the Zone System... I'm working on the points system. First I points it here, and then I points it there...