The full article on how to setup a PBN is here: http://passivejournal.com/how-to-build-pbn/
This video will teach you how to find expired domains. Finding expired domains is a tough task if you do not know how to go about it. This video explains the whole process as easily as possible. Expired domains is a great way to build your PBN. You have the alternatives to buy ready-made expired domains but that will cost you a lot of money.
Finding expired domains like the way I showed is probably the easiest and the least costly method.
Let me know whether you guys see any positive results from this video. I would love to know.