<human>: How can I make a sourdough starter?
<bot>: To make a sourdough starter, you will need to mix equal parts of water and all-purpose flour. Stir the mixture until it is completely combined, then let it sit for 12-24 hours at room temperature. After that time, you should start seeing signs of fermentation such as bubbles forming on the surface or an acidic smell. Once these signs are present, your sourdough starter is ready to use!