Sourdough Starter Recipe:
2 cups whole wheat flour
2 t. sugar
2 1/4 t. active-dry yeast
2 cups warm water
Mix the flour, sugar, and yeast in a clean, 2 qt. capacity glass bowl.
Gradually stir in the water and mix until it forms a thick paste and do not worry about lumps. Cover with a dish cloth such as this one from Evelyn Fields
and let sit in a warm, draft free place.
Once the starter is bubbling, feed it daily with flour and water while removing a cup of starter. You're just replacing it. I have been using 1 cup of flour and 1/2 cup water... still working on this one though.