How do I cram AP European by the exam?

For some context: I've essentially ignored the course material for this last semester, and I was barely able to pass it by guessing on the tests. I have absolutely no understanding of the different essay questions. That just leaves me with a fraction of the time the other students had to actually understand it.

I have several AP courses lined up for my Junior year, and I'm VERY reluctant to register for APUSH with my abysmal outlook for this one. I at least want to get that credit for European.

Are there any recommended studying materials that have worked well, and what am I looking at for the next two months?