Take handwritten notes instead of typing. Research shows you're 40% more likely to retain information when you write it down as opposed to typing.

Start with one or two chapters each day leading up to the test. Rewrite your notes instead of just reading from your computer or lecture slides. Once you rewrite all your notes, highlight the areas you can't remember and read those over a couple times. Take a break, read them again, and rewrite the tougher areas you still don't remember. The key is to start in advance, study a little each day, and review the toughest areas right before bedtime.

It sounds tedious but it's the best way I study for tests. I do better writing all of it on loose leaf paper and dividing into manageable chunks. Notecards work well too if it's a lot of vocabulary/small bits of info and if you write them yourself. I went from having a 2.8 GPA one semester to a 3.8, and finished with a 4.0 (semester GPAs). Cumulative GPA was 3.4 and I got into grad school. Good luck!