Put the milk in a sealed container (I use a locked box) and microwave 1.5-2 minutes. Take it out and wait until the milk temperature reaches about 40 (my method is not to burn your hands). Pour in plain yogurt and sugar (or put sugar when yogurt is ready to eat). The ratio of milk to yogurt is about 8: 1 (you can add more yogurt if you like strong acid). Clean chopsticks mix milk and yogurt evenly and put them into the rice cooker. Put 1-2cm hot water into the rice cooker (the water temperature is slightly hot), cover the rice cooker cover, and cover the air outlet with a cloth. Don't plug in the rice cooker during this period. Try the water temperature for two or three hours If the water is cold, plug in the rice cooker for half a minute, and then pull it out when the water is slightly hot. It takes about 8-9 hours to make yogurt. Just put it in the refrigerator. This is how I successfully made yogurt. Hope to adopt ~ thank you ~! !