Start studying the first day of class. A semester-long college course is not designed to be mastered in one night before the final. If you are going to do well on the final, you'll have to be sure you take the time to process what you learn in each class. Daily review is the first step in preparing yourself for the final.
Reach out to the professor prior to the final if there is something you don't understand. Your can visit your professor during her office hours to clarify things that aren't resonating with you. She can help you to get a grasp on the material so that you understand the information you will later see on the final.
Start a study group during the semester. Studying with your peers is an excellent way to prepare for a college final. You can reinforce concepts for yourself as you clarify information for them, and the same is true in the reverse. As you work together, you learn with and from one another.
Request a review session from the professor. If your college professor is willing to host one, taking part in a review session prior to the final is an excellent way to prepare. Use the session to outline those things that you feel confident that you know (and thus do not need to study) as well as those things that you have not mastered (and so need to study.)
Practice writing about the concepts you have learned in class. Many college finals are comprised solely of essay questions. Anticipate what questions your professor might ask and study for the final by writing out your responses. Ask a fellow classmate to look over your answers and make suggestions about what (if any) additional information you should include in your answer. Your professor won't necessarily ask you the same questions on your final, but in anticipating these questions, you will be well prepared for any questions she may ask.
Make flash cards for yourself that include key phases, definitions and concepts you have learned throughout the course. Flip through them often as a way of testing yourself. Use them as a guide to help you determine what you'll need to spend more time on as you review your notes and class materials.