When I come back to the former book I go through the chapter again creating Anki cards for anything notable. The sheer amount of material I notice I had completely forgotten on the second reading is astounding.
I go through the Anki cards daily, in the morning I cover the material created from two of my books. In the evening I go through the third book (which I deem more valuable in a deep sense/abstract).
I have yet to have solid a strategy on chunk-building (as the course pushes you to do), however I can still see some bigger units emerge with time.
It is the process of recall that makes things stick to memory as opposed to repeated memorization. Working on several subjects at a time spaces out sessions and prevents the illusion that you have access to the knowledge you worked for when in fact you don't.
[1] http://metamodern.com/2009/05/27/how-to-learn-about-everythi...
[2] http://metamodern.com/2009/05/17/how-to-understand-everythin...