4. Wait
Now you have to wait. You’ll need to have good patience if you plan on making some sourdough bread. You might be wondering what it is that you’re waiting for. Well, you’re waiting for your starter to come to life.
You’ll know this has happened when you see it bubble. As time passes, you’ll see it grow in size and rise to new heights. Waiting for sourdough starters to ferment is like watching a child grow up — except you’re going to burn and eat that child as soon as it reaches adulthood.
I bet you want to know how long you’ll have to wait. The sourdough starter usually becomes active within 12 hours, so you can leave it be while you handle other tasks like working out, showering, or eating some regular bread.
If it isn’t active after 12 hours, give it another 12 hours. If it passes the 36-hour mark and still isn’t active, check that you executed the previous steps properly.