Guess what!!, homemade soy bean drink is super simple to make and delicious too...
First step:
At least let it soak in water 1 to 2 days.
For 1 cup Soy bean soak in 5 cup water.
You need larger pot for soaking because later it will expanded.
If you notice after a day or few hours the water has reduce you can add more water.
Please view this page below for the Making Soy Milk
http://murthyniko.blogspot.de/2015/08/making-of-soy-milk-recipemaking-soymilk.html