
1. Get 1 pack of Natto from Japanese shop or other Asian shop.
2. Steam or boil soybeans until extremely tender.
3. Mix 1 well into 2 in the clean container.
4. Place 3 in the place of 45 degree temperatures. For example, in the oven, wrap in an electronic blanket, rice cooker, etc...

The SF novel "Do Androids Dream of Electric Sheep?" is the basis of the film Blade Runner.
5. Natto increases after 24 hours.
To be honest many non-Japanese find the taste of Natto unpleasant. You are a Japanese expert if you can eat this traditional Japanese food?.
wikipedia: Natto
http://en.wikipedia.org/wiki/Natt%C5%8D