First, soak the soybeans in water for one night, grind the soaked beans, add water to squeeze out the soybean milk, boil the soybean milk in a pot, and pour it out (at this time, pay attention to the fact that the boiled soybean milk is easy to overflow, and act quickly), and then order the brine tofu (don't put too much, otherwise the tofu will be very old and the brine will be toxic, but the calcium in the tofu mainly comes from this, so you can eat it safely). At this time, you can see that there are small pieces in the soybean milk (large pieces indicate that the tofu is old, so the brine should be put bit by bit, while stirring). Pour the massive soybean milk into a piece of coarse cotton cloth and wrap it, and the water will separate out. After a while, the tofu will form a large piece.