Measure out your starter on a digital scale. You want equal weights of starter, flour, water.

Note the weight of your starter and zero out the scale.

Add the same weight of water and zero out the scale.

Add the same weight of flour.

Stir well to combine then place the fed starter in a jar. Cover with a piece of cheesecloth secured by a rubber band.

Note the level of starter by drawing a line on your jar or by placing a piece of colored tape at the starter level.

Put the jar in a warm spot. If it doubles in 12 hours, you're reading to bake. If it doesn't double, you'll need to feed it again.

To feed again, discard half the starter, weigh the remaining starter, and begin the process over again.

Keep the discard in a covered jar in the fridge.