You'll need a small clear plastic container--probably one that's about 8-12 ounces would be ideal. You'll also need water and flour. The book suggests a wide range of flour options: bread flour, all purpose flour, white/wheat flour blends... All should work well enough for developing the initial culture. I used the half and half mix of white all purpose flour and whole wheat flour.
If you have a scale, maintaining the starter is a little easier. For the most part, you'll be adding equal weights of water and flour. For the initial mixing, I started with about 3 oz each of the flour blend and the water. Mix this in a container until it's the consistency of a THICK batter. (I did it wrong the first time and ended up with something way too watery for the first few days--even so, it was easy enough to recover.) You can mix with either a spoon or your hand. Hands are suggested for the first mixing, so that the starter can take advantage of the wild yeasts that are naturally on the surface of the flour and the baker...
You'll want to cover the container with a clean kitchen towel or a washcloth, and put it somewhere dark and fairly cool. I used a closet. Weird but effective. Check it after about 2 days. It should start looking fairly active by then--if not, give it another day. This is what mine looked like after 48 hours:

Note: it smelled far from pleasant after the first few days. It was beginning to overpower the apartment, which was not ideal--I was worried my home would smell like that eternally, but after a few feeding cycles it stopped being noticeable.
The starter needs to be fed about once every 24 hours. For me, the process was something like this:
1. Using a spoon, lift off the top layer and discard. Then discard more of the starter until you're left with about 20-25% of the original volume.
2. Add equal parts flour (whatever flour option you originally used) and water--I ended up doing about 1.5 oz of each for the feeding.
3. Stir until it resembles a thick batter again. Cover, and replace in a cool dark spot.
Start to learn what it smells like before and after the feeding, and make notes of its appearance, too. It took about 2 weeks for mine to start smelling recognizably like bread, and for the culture to behave the same way every day. Once that's happened, it's usable.
Now that I want to be making bread regularly, I'll need to keep up the daily starter maintenance. The idea that these cultures can become many years old is both creepy and totally awesome.
I just wrote a fair amount about the starter, but it's only a fraction of the material they present about the starter in the book--for all the facts, you may want to get your information directly from the source!


