What works for me (I apologize for any bad grammar, typing from my phone):
1) Sit in front of class so I'm not distracted by other students
2) Type notes onto PowerPoints professor uploads. If none are uploaded, I try to type all the important points the teacher says word for word. Really helps if you're a fast typer so you can get all the tiny details.
3) I review the notes the day after lecture and dissect each point and try to draw connections and understand the purpose of each slide.
4) at the end of the week, I go through all the powerpoints and notes in one sitting as a review. Spend extra time to make sure you understand everything. Email the professor if you are missing any concepts, Google if you need to (videos are often very helpful if you are a visual learner such as myself)
5) repeat this each week, don't go back and study the previous week again unless you really need to or have time on your hands.
6) the week before the exam, begin reviewing all the slides and notes collectively. Try to do first half of the content in one day, second half of the content the next day, and repeat until exam day. IF you have the stamina, do the entire content in one day.
7) glance through notes on exam day for no more than 30 minutes-1hour. Get a good meal in and STAY HYDRATED (dehydration can really ruin your ability to recall information you've clearly memorized).
Moral of the story: quality notes and quality repetition are ABSOLUTELY KEY. This is factual. If you don't want to blank out on exam day, repeat repeat repeat. If you really need to, make study groups, although I've personally found them to slow me down and are a waste of time unless you'd like to help struggling classmates. You can handle it yourself. Perfect practice makes perfect!
Evidence: I've maintained a 4.0 with a computer science/molec bio courseload and whatnot throughout my junior and senior years with 18+ credit hours. Not bragging, please don't drill me SDN lol
I hope this serves you well. Just remember, this is how I do it and there are certainly other ways. You need to find what's best for YOU.