my scores went up with time - learn your professor well. While everyone here gives you great advice, likely your professor will have a very narrow view and way of teaching. So learn his patterns. and how he tests. The format. Some had multiple choice, the majority have fill in the blank. maybe a mix. But the extent and the type of questions for your specific professor - that will be the most important.
Your best bet is to get hands on past tests. Or talk to someone in detail who has taken him before.
Other than that: practice, practice, practice. The idea of things settling is so still kind of funny, but could not be more true. You wake up 3 days after hammering a topic and learn you know something.
Here are a few more off the top of my head:
1.) HNMR is no joke. You will need a lot of practice with it.
2.) dont neglect the easy sections. They are good point boosters.
3.) go to class. Hints are often dropped about test material.
4.) practice every day for a few hours
5.) Before you go to bed go through a mechanism. and sleep on it. Let it be the last thing u think before sleep.
6.) make flashcards. they help.
7.) second language helps. But its made for every single student out there. you will often see "check what your textbook says". My friends treated it as a holly grail. and neglected the specifics the professor wanted. the type of specifics that show from a professor's personal experience with the material.
8.) dont pay attention to what other people are doing. My classmates did 150 hnmr problems a day. Others only read second language. Listen to what works for YOU.
9.) Wade organic chemistry is a golden classic. Its solution manual is amazing too. Its also cheap cause fairly old. But the principles havent changed.
10.) if you are taking the ACS exam at the end. Get the study guide now. Not later. Go through it as you cover material. Sometimes teachers get exact type of questions from there.
Good luck !