Submitted by Eric
Combine the vital wheat gluten with hot water in a bowl. Use just enough hot water to get all the gluten flour wet. Knead the mixture with your hands. It should form a big sticky mass. If it's not holding together well, that means your vital wheat gluten isn't fresh. That's not a major problem, it just means you have to knead longer. When the gluten is holding together fairly well, pour cold water into the bowl, and continue kneading. The water will turn whitish. Pour out the water when it is white, and get more cold water. Repeat this process for a while - you are washing the starch out of the vital wheat gluten, so that it becomes more protein-rich. Don't do it too many times, however, or the seitan will be too tough. Experiment with this a few times, and you will know when to stop rinsing. When you are satisfied with the results, it's time to cook the seitan.
To boil the seitan, just bring some broth to a boil, tear the gluten into small chunks, throw into the boiling broth and boil for 1 1/2 - 2 hours. Good broths for boiling seitan are vegetable broth, mushroom broth, or just water with soy sauce.