This article is from the Sourdough Starters FAQ, by Brian Dixon briandixon at hotmail.com.
* Combine 1 cup starter, 1 cup 80-85 degrees water, and 1 1/2 cups
all-purpose flour and/or other ingredients (throw in some cracked
wheat, or substitute part of the flour with cornmeal or rye, etc.)
* Proof the starter for 8 to 12 hours (mild flavor, more active) or
up to 48 hours (strongest flavor, weakest action) at 85 degrees.
Recipes requiring the yeast action should either use shorter proofs,
or cooler (72-80 degrees) proofs if proofing for a longer period.
* Concurrent to the above, replenish the starter in the container
with 1 cup 80-85 degree water and 1 cup all-purpose flour. Proof for
8 to 12 hours at 85 degrees. Refrigerate.
 
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