I usually boil a 900 g bag of dried chickpeas for about 1 hour, with a tablespoon of vinegar added. Then I place the chickpeas into a large colander for them to cool and dry, and then I disperse a tablespoon or two of "starter" on them. I then put about 300 g - 400 g of inoculated chickpea into perforated ziploc bags, and hang these bags using clothpins in a 'chamber' that I made (it is a plastic tub with insulating foam, a hole through which a ceramic bulb heater goes in, and a cheap temperature controller that controls the chamber temperature to around 30 C).

This is a photo I have from a recent (FAILED!) experiment trying to 'scale up':

And this cover goes on top:

Imagine this, but with half the amount of tempeh. In this experiment I tried to make !3.55 kg of tempeh at once (8 tempeh), but they were touching each other, and the contact points of the tempeh turned wet and acidic - either it became too hot, or poor airflow allowed the bacteria and not the fungus to dominate those areas.