I thought studying meant spending time reading. But instead of actually learning, I was just trying to remember what I wrote on the pages.  
That made me realize that I needed to change the way I approached learning.  
So I focused less on just reading and more on testing myself on what I could actually remember  
Flashcards: I stopped flipping through them mindlessly. Now I look at the question, try to answer first, then check if I was right. The ones I miss are the ones I keep seeing. I use Turbolearn for mine.

Cornell notes: After class I'll go back through my notes and turn the key ideas into questions. Later I cover the notes and see if I can answer everything without looking. It feels a lot more active than rereading.

Quiz yourself before studying This felt stupid at first, I'll look at the questions at the end of the chapter before I've even started and take a guess. I get almost everything wrong, but when I study afterwards the information sticks better. I'll also throw my notes into Turbo to generate extra practice questions.

Short study sessions over a few days I'd rather study a subject for 40 minutes a few times during the week than do one huge session. Before opening my notes I always try to remember what I already know first.

Explain it without sounding smart If I can't explain something in really simple words, I probably don't understand it yet. That's usually my cue to go back and fill in whatever I'm missing.

That’s pretty much what’s worked for me. I still reread sometimes, but now I try to make sure  
I’m actually recalling something instead of just staring at the same page again. What do you guys use when something just won’t stick?

I spent years studying the wrong way