In order to make yogurt at home, you will need milk and
some yogurt for ferment (1 tablespoon yogurt will be
enough for a liter of milk). Boil the milk in advance and let it
cool to a temperature of about 42-45° C. If you don’t have a
thermometer, you can dip your little finger in the milk. It is
suitable for souring if it is not hot and has a pleasant warm
temperature.