The next step annotating the book. I have a color coding scheme that I use across all of my notes. Pink is also a variable definition, red is an example problem, etc. When I'm taking notes at this stage, it's so that I can quickly go back through the textbook and figure out what the main ideas are. I do this inline with the text, so there'll be something like "Nernst Equation---->" so it's easy to find it later on. With English books, I'll also have a summary at the beginning of this chapter telling me what happened in the chapter. It's usually pretty easy to figure out what's happening in a given chapter of a textbook, so I don't do this.
Depending on the complexity of the subject / how lazy I'm feeling, this is where I'll end. I have some classes that assign fuck tons of work, so I just annotate my textbook well then work through the problem set. For things that are more conceptual (and I'll want notes to review from at the end of the year for finals) I'll take separate notes on paper. This time, I read the textbook through for the 3rd time. This time is pretty fast, mostly just writing down what I wrote in the margins the first time. Generally by this stage everything is in my own words, but even if it's not, I know that I understand it (or perhaps more importantly, I know what I really don't understand by this point and then