@HGFitz
My biggest advice would is don't be afraid to utilize different studying methods for different courses (if you need to). Otherwise if you are struggling and continue to utilize the same method constantly, then you will continue to bang your head against the wall with no improvement. For example, I used to practice Organic Chemistry reactions on a class whiteboard with my lab partner and we would discuss different ways of going about the scenario at hand (this helped for critical thinking on exams). However in a course like Microbiology I would usually just read the textbook and write my notes in themes which organized the content more efficiently for exam preparation. So try to mix and match depending on what works best whether that be flash cards, working in small groups, text book notes, or a combination of all three, it is your time to work at it.
Also, please go to office hours and utilize your resources if you need help, because that can honestly clear up a lot of questions while you're studying as well.