If your class has online lecture slides, print them out and take notes on those, then study them for exams, you will/should get good scores everytime. I found writing notes from the books to be a waste of time unless I KNOW the professor teaches straight out of the book, but even then, many professors skip sections or chapters, so if you took notes on those and studied, you have wasted your valuable time.
Note cards and such are a waste of time if you have a decent memory, because the time you would use to write them all out on note cards, you can prob go over the material 5 times. However, some stuff are better visually, and consolidating important info into a study guide is very helpful (for example, O-chem reactions), in those cases a few flash cards will help.
Finally, MANAGE YOUR TIME WELL, know your limits, studying for 10 hours while you are distracted every 10 min. and studying for 2 hours while focused are very different. Study hard, study smart, and don't waste time. Work out a system and know when you need to start studying for particular classes.
And good luck, keep your eyes on the prize and you will be fine 🙂