Right, just looking over them is not enough. The Cornell system of notetaking is much better, and proven effective. Take notes in a looseleaf notebook, with a page number or date on each page. A much better variation in the left "cue" column is to write a question about the notes content, then you can review the question column as a study guide. If you know the answers, move on. You don't need to buy special paper, just make a vertical line on the left side before you use each page, dividing it into a cue section, and a notes section. You can use this same notebook and method for text notes. When studying the notes, take the pages out, lay them on top of each other overlapping such that you only see questions. If you don't remember the answer, lift up the paper covering the notes part.
My handwriting was soooo terrible, that I developed a METHOD. I would come back to my desk and immediately "translate" my scribbles into an organized outline. In the process of doing this I could "re-hear" the lecture and add information that I thought pertinent in an organized manner. Then when it came time to study for an exam, I had all the information outlined and accurate.
Again, I recommend questions in the left column. Notice the last name on the cue column: I would recommend change that to a question, as "who is xxxx?
instead of define, "what does xxxx mean?
Make it like a test.
I am not so hot on the summary section at the bottom, I learned to use, and later teach, skipping some space between ideas presented in lecture, and using that space for a short summary, or editing outside of class. Putting it at the bottom of the page just breaks the continuity for me.
Now when do you use these notes: Just after class, read, review, and fill in the question column. Later, within 12 hrs, go over the notes and questions. Within the next 24 hrs, just review the questions: do you know the answers. Then, in 2-4 days, go over the questions again. Then when studying for tests, you will find you have "test" questions already generated, and you can study them, and surprisingly, you know the answers.
We learn by repetition spaced over time.