All items used here should NOT also be used to prepare food.
Materials you will need:
Yarn - I got mine at Dharma Trading, 75% wool, 25% nylon fingering weight (sock yarn)
Dye - I used Jacquard Acid Dyes
Distilled white vinegar
Synthrapol (available at arts & crafts stores; I got mine at AC Moore) or Dawn dishwashing liquid
Small tub for soaking
Plastic wrap - my sources recommended brand name (thicker ply)
Measuring spoons - plastic or stainless
Little containers for the dye
Sprinkler or spray bottle
Microwave oven (ideally an extra one, not one you use to cook food in)
Step 2: Soak yarn
Step 3: Prepare work surface
This would also be a good time to write out your instructions, and put them up on the wall. Years ago when I took organic chem lab they made us write out the lab instructions prior to performing the experiments, and I found this to be a very helpful preparatory step. Also actually referring to your instructions as you go is a good idea.