1. Day 1: The Beginning: In a clean, clear glass jar (a quart-sized mason jar works well), combine 1/2 cup of unbleached all-purpose or whole wheat flour with 1/4 cup of filtered water. Mix thoroughly with a fork or spatula until there are no dry spots and it forms a thick paste. Scrape down the sides of the jar, cover loosely with a lid, plastic wrap, or a clean kitchen towel (allowing air to circulate), and leave it at room temperature (ideally 70-75 F) for 24 hours.

2. Day 2: First Feeding: Discard about half of your starter. To the remaining starter, add 1/4 cup of flour and 2 tablespoons of filtered water. Mix well, scrape down the sides, cover loosely, and return to room temperature for another 24 hours.

3. Day 3-7: Daily Feedings: Each day, discard about half of the starter, then feed it with 1/4 cup of flour and 2 tablespoons of filtered water. Mix well, cover loosely, and let it sit at room temperature. You should start to see bubbles forming and a yeasty smell.

4. Observing Activity: Your starter should become more active after each feeding, rising, becoming bubbly, and then falling. It should consistently double in size within 4-8 hours after feeding and be full of bubbles.

5. The Float Test (Optional but Helpful): Drop a small spoonful of starter into a glass of water. If it floats, it’s active and ready to bake with. If it sinks, it needs more time and consistent feeding.

6. Maintaining Your Active Starter: If baking frequently, feed daily at room temperature. If baking less often, store in the refrigerator and feed once a week. Remember to take it out, feed it, and let it come to room temperature and become active again before baking.