Soak the soybeans in water for at least six hours or even overnight.
Add the soaked beans and water to the blender. (The ratio is one cup of beans to two cups of water). Blend in batches until it is smooth and creamy. That yields soy milk.
Once you’ve blended your soy milk, use a cheesecloth or strainer to strain out the pulp from the soy milk. Skim any foam from the top of the drained liquid as well.
Transfer the drained liquid to a pot and simmer for about 15 minutes. As the milk is simmering, watch it carefully and skim off any foam as this could affect the tofu’s texture.
Once the milk comes to a boil and is foaming heavily, remove it from the heat and add your coagulant (if you are using gypsum, dilute it with water first). Stir the mixture a few times and you should notice curds forming. If it isn’t curdling yet, add more coagulant and return it to the heat.
Let it sit for 15 minutes.
Put a cheesecloth in your mold and place the mold on top of a tray or something to catch the draining liquid. Put the curds inside the mold and wrap it completely with the cloth. Put something heavy on the tofu to press it.
Let the tofu sit in the mold as desired, depending on the texture that you are trying to achieve. (For firm tofu, let it sit for several hours.)