Study with the syllabus next to you. I would recommend having a read through an Excel book, as they cover each topic well in summarised points. I.P.T. is more content based, so basically you have to know each topic pretty well. Also have a look at your own notes too.
Could not agree more. The Excel book helped me immensely in the final few weeks before the HSC exam. By that time I'd had enough with the Samuel Davis convoluted garbage that took pages to explain a concept Excel did in one paragraph. Never regretted that purchase - ended up getting a final score of 92 after what was mainly games in our classroom for the best part of two years. The syllabus is also key so you know exactly what the exam will be assessing and what you need to look out for.
That being said, however, if you want to get some extended response language and ideas, Davis' textbook is great for that. They're also good with representation techniques. Practice doing a few dataflows and flowcharts because you're guaranteed to get them in the exam.
I'd just like to point out that personally I didn't write a whole lot of my own notes. Never really got into the habit of doing that for any subject, as I felt like I was wasting time writing them up rather than actually studying them. But writing your own notes is also a good idea to at least try if you haven't already done so.
After you feel like you know enough, try doing some questions from some past papers to see how you can apply that knowledge.
Good luck!