Combine whole wheat flour and water in a glass jar and cover loosely.
60 grams whole wheat flour, 60 grams filtered water
Day 2:
Observe starter for bubbles, which may or may not be present. Let starter rest for another 24 hours.
Day 3-6:
Discard approximately half of the starter and feed with 60 grams unbleached all-purpose flour and 60 grams filtered water.
Day 7:
If your starter has doubled in size and has plenty of bubbles, it's ready to use. If the temperature is too cold in your house, the starter may take up to 2 weeks to activate and be ready to use.
Storage:
You have two options, on the counter or in the refrigerator. If you store your starter on the counter because you bake often, you'll need to feed it everyday at the same time. If you store your starter in the refrigerator, you'll need to feed it weekly on the same day, at the same time.
Notes
*I don't recommend baking with the initial set of discards from the first week. Let the starter fully activate before using the discard.