First: soak 1 cup of dry soy Beans in 3 to 4 cups water overnight or until soybeans double in size. Drain water. Put 1 cup soaked soybeans into blender. Add 2 to 3 cups water and blend until of mushy consistency. Empty into a large pot. Continue blending soybeans with water until all have been chopped.
Place pot on medium heat and bring to almost a boil. When the mixture starts to boil, turn heat down to low and set timer for 30 minutes.
Take the white liquid (soy milk) and place back on heat and pour 1/4 cup lemon juice and stir. When this mixture begins to coagulate, you have what is called "tofu" or curds and whey. The curds are tofu and the whey is the liquid.
The okara is fiber. You can spread this out on a cookie sheet and dry in the oven on very low temperatures. Then you can add to gravies, etc, you can think of to hide it in.