None, really. Most of the Commercial maneuvers are far more about "feel" and "doing what it takes to make it work" than you're used to from the instrument rating. Videos can help some, but to me nothing beats going up and seeing them demoed, then trying them. They are very easy to overthink (especially Lazy 8's), but once you see them it all kind of clicks better in my experience.
Trying to read about how to do a Lazy 8 is likely to make your head explode.