Add 1 cup of flour and ½ cup of warm water (if your water is heavily chlorinated or unfiltered, use bottled water) Chlorine retards the starter and can affect it.
Stir then cover. Let this sit at room temperature until all bubbly (about 3-5 hours)
Once bubbly, stir it again and pour it into a 2qrt glass jar and cover with your “holy” lid.