I've finally got a study-rhythm going, and the key to doing so was being able to find what works for me.
For me, I go back over every single set of class lecture notes and rewrite them completely from my understanding. It's as if I'm teaching myself what I learned, and I rewrite everything in my own words, draw pictures to better visualize what's going on, and color-code everything and add markers and flags to every major section that's going to be on the test, separating things into chapters.
The downside to this is that it takes FOREVER. I spent 7 hours absorbing and rewriting two chapters of Chemistry. But it's okay, because regardless of the grade I made on my test two days ago, I KNOW I can explain to you and teach you exactly what the material is over because I've learned to study this way..
I plan to pursue this technique, the problem is, I'm behind. I need to do it for some older Math and Chemistry notes, but we've already moved on to the new stuff, and I have a History test tomorrow that I need to finish preparing for.
I'm going to spend as long as I can trying to catch up, and then when I'm caught up, I'm just going to review everything we've learned weekly by re-analyzing the chapters at hand.