Pre-reading/preparing for the next day's lectures is a complete waste of time. I repeat, a COMPLETE waste of time.
Just watch/attend that day's lectures, study those powerpoints in depth that day to the point that you'd be ready to be tested on it the next day, and you're good. Pre-reading/looking over thepowerpoint before lecture is a waste of time. Just make sure you're caught up on everything leading up to that material. Attending/watching lectures should be the first time you're exposed to that new material.
And as others have said, don't use other textbooks. Powerpoints, wikipedia, Step 1 material, good to go. I just felt I needed to post this since no one else has mentioned how pre-reading is a waste of time and poor use of your time. Technically, if you are pre-reading/studying, then there's no point in attending lecture period. I would highly discourage this method, though, since lecture often adds in new notes not included on the powerpoint. Because of that, pre-reading is a waste of time and you should count on first exposure to be during lecture.
It won't hurt you if you preread, but it's just an unnecessary waste of time. Have I stressed that enough yet? haha