True as it might be that it is too late to make study notes, if you have summaries of your subjects, it can still be beneficial to read through them (like when you're on the way to school, before bed). At this stage in your revision, you would optimally be doing practice exams whenever you can (after school, in school, etc), but if you've got time where you can't do that, and you already have study notes, do go through them. These will also come in handy for when you are marking your practice exams, if there are things you've forgotten/don't know/got wrong, see if you can find them in your notes, study them.
However, if on the alternative, you don't have prepared study notes already, as _fruitcake_ already said, it is too late to create in depth summaries for everything. In that instance, what I recommend is when you mark your completed practice exams, many students create a "log book of errors" so to speak. Basically, its where you note each exam that you do (don't have to, just what I do), I'd write my scores for each exam I do, and then summarise what you've got wrong, and from there you want to write what the correct answers are, and use that as a revision tool as opposed to the notes I mentioned earlier. So when you're traveling or in bed, go through your log books and find your most common errors and study the correct answers.
But directly answering your question, practice exams are the most effective means of studying, because they are going to highlight what you need to know/what you should know, what you don't know, how the expression of your answers will get you marks in the exams, marking papers will give you an indication as to where you're aiming, what questions score what marks, etc. The exam is what matters, so exposing yourself to as much of those styles of questions is what is going to help you become familiar and comfortable with the exams you're going to be sitting.
Best of luck
