You will have better luck searching google (or youtube) for "how to breed black solider fly larva"
Lots of information out there. Basically though, if you are not in the proper zones of the world for them to breed, you likely won't have much success, as you do have to keep them outside, and let the flies loose.
You provide the compost bin, and the flies will stay (or at least keep coming back to deposit their eggs).
-Brandon