Go to all of your calculus lectures. One of the best things you can do to help your overall grade in calculus is to attend every class. If you don't plan to do study outside of class, you can learn all of the material that you will need for exams by simply being in class.
Pay attention to your calculus professor during class. You will want to try to get as much out of your class as possible, so stay focused and don't let your mind wander. Try to get a firm grasp on all of the topics that your professor covers during class.
Take detailed notes during class. If your professor goes over steps on how to solve calculus problems, write these down in your calculus notebook. Also, write down any sample problems that your professor does during class. Writing down material will help you remember it for your exams and quizzes.
Ask your professor questions while you're in class or after class during your professor's office hours. Since you aren't going to study outside of class (which would help you be able to answer your own questions in most cases), you will want to have your questions answered by your professor if you can.
Try your best to read your calculus textbook. You don't have to put a lot of effort into this. You just want to skim over your book at a minimum. Usually, your professor will cover the material in your book in class, but if you can, reading your book will be helpful.
Do calculus problems that are assigned to you, like those in your homework assignments. If homework contributes a percentage of your final grade, you will want to complete your homework assignments to the best of your ability. Doing well on homework will help you get an overall passing grade for your calculus class.