Here are a couple of tips for taking notes in the class.
Do not just write down what you see on the board. No instructor is going to write down every word they say and sometimes the important ideas won’t get written down.
Write Down Explanatory Remarks.
Make sure you write down any explanatory remarks the instructor makes. These often won’t get written down by the instructor, but can tell you how to work a particular kind of problem or why the instructor used one formula/method over another for a given problem. Note Important Formulas/Concepts.
If an instructor emphasizes a particular formula or concept then make note of it. This probably means the instructor feels that it’s important and important formulas and concepts are much more likely to show up on an exam. Question Your Instructor.
If you are unclear on something ask questions. Note Topics You Don’t Understand.
If you are having trouble understanding something being presented note that in the margin and at least write down the key words. Leave yourself a couple of lines so you can fill in the missing details later once you’ve gotten help to understand the concept. Review/Edit Your Notes.
As soon you can after class go back over your notes. Look for any errors and/or omissions. Fill in any information you didn’t have time to write down in class. Review Regularly.
At regular intervals sit down and review your notes so that you can learn and retain the information. Remember, that this information will probably be required down the road so it’s best to learn it as soon as possible.