Drain water and rinse well. Cover the lid with a mesh screen or something similar. Keep the jar side way and wait until they spout for one and half to two days. Pour water and drain water to moist wheat berries at least a couple of times a day.
When you see the tali, pour 2 cups of water in the jar. Loosely cover the lid with a piece of paper towel or plastic wrap.
Taste rejuvelc every day. When it tastes tangy like yogurt (a couple of days for me), pour the water into another jar. This is the first batch. Store rejuvelac in the refrigerator.
Pour new 2 cups of water and repeat the process. It takes a couple of days for me to make each batch. After you have the fourth batch, discard wheat berries.
Note: This whole process will be done at the room temperature. Store rejuvelac once it's made in the refrigerator.
Recipe by Asian Vegan & Beyond at https://www.asianveganandbeyond.com/rejuvelac/