Soak soybeans in water for at least 8 hours.
Rinse the soaked soybeans thoroughly.
Add the soybeans and water to a blender and blend until smooth.
Strain the blended soybeans using a cheesecloth.
Pour the strained soy milk into a pot and boil over medium heat for 10 minutes.
Add a pinch of salt or sugar to taste, and it's ready to serve.