You should follow the study plan provided with the course. Watch the videos and keep making notes. Keep revising the notes on the revision dates. In case you don't understand the notes, go back to the lecture.
The only notes that can help you in this exam are the ones made by you. We want you to consume the lectures in double the runtime of the videos. You must keep pausing the lectures and keep scribbling your notes.
Ideally you should start at least 8-9 months before the Prelims date. If you are late, you will have to put in extra effort and will have to study very regularly.
There may be two reasons for such a thing. First and most likely is that we have deliberately skipped that topic as it takes a lot of time and carries very little weightage in the examination. Secondly, if we have forgotten to cover a specific topic, you must immedately let us know. We will cover that topic as soon as possible.