Honestly, you will find far more info by using the custom search. I spent a good part of the winter months reading hundreds of posts on homemade incubators:
found a guy who made his own turner using a grid made of wooden slats. (Think Christmas ornament storage box).
many way to heat; thermostat recommended; many details to consider.
where to put the ventilation holes
ability to alter humidity levels.
IMO, read a bunch, try Miss prissy's page too.
GOOD LUCK and have fun!