Dim, Darkroom

For gum bichromate and most other alternative processes you don't need a darkroom, but a dimly lit room. If you must have a light source use a tungsten bulb with a low wattage and direct it away from your work area and where you dry your prep paper to prevent fogging the sensitized paper.

Setting up Chemistry

You will need several water colors available and the same number in glasses to measure out the required amounts per layer for your image. This will be the same for the eye droppers and brushes. Gum bichromate uses gum arabic and ammonium dichromate. Both of these and the colors can be ordered: Contemporary Gum Printing Kit from BH Photo.

Layout

For the layout, you should have all your supplies in a dry area, the paper that will receive the gum bichromate layer(s), bushes and paper towels arranged as you like. All on top of newsprint and cardboard to prevent transfer of chemistry and keep the space clean.