What is Xenesthad is referring to is "link cloaking" or referer hiding. I personally don't call that cloaking. link hiding is easy. its just rewriting a url. nothing fancy.
Real cloaking is much more advanced then link cloaking. With cloaking you are delivering different content to for example a spider bot and a real website visitor. There are many different ways to do some proper cloaking. Usually its IP and User agent based. But you can also cloak geolocation, organization and other identifiers like behavior. If you plan to do cloaking I would advice you to do some extensive reading and testing. Bots, spiders, manual reviewers change their tactics all the time to catch the cloaked sites. Therefore there are not many (seo, ppc) cloackers out there, because the risk of being slapped is high.
FYI Any technique you can find here is propably already known by G. So be creative. They probably also learned here about it first. Or any other blackhat forum.