If you don't have an Instant Pot for the incubation: Place the tempeh bag on a baking sheet and put it in the oven for about 20 hours at 86°F (30°C). My oven can go to a low temperature, but if yours can't, just let the oven light on or use a dehydrator set at around 86°F. Be aware the incubation time can take longer if the temperature is too low.