How to study for 4 AP exams in one year?

So as a freshman I only took human geography. Got a 5. Right now as a sophomore I’m in AP euro. That’s an easy A. I will probably get a 5 or 4. But next year I am signed up to take AP stats, macro, psychology, and US history. I’m not used to doing more than one exam and I’d usually just buy the Princeton review guide and read it the week before the test. So I’m wondering what you guys do/would do? Should I just buy 4 Princeton review guides?

My ds had 5 ap’s last year. He worked through each of the review books (researched best book for each class) as the year went along in each class, reviewed the book and took practice tests in the few weeks leading up to the test and then took the exams. Best way to do multiple imho.

My strategy was to study hard for class and keep on top of my work and the pace we were doing in school throughout the year. In April, I spent 2 hours studying for AP exams every day and would have A and B days that alternated. On A days, I’d review material for half of my exams and do practice questions for the other half. On B days, I did practice questions for the exams I reviewed the day before and reviewed for the exams I did questions on the day before. For review, I’d read over notes, watch YouTube review videos, or read through a review book. I’d only review about the first 50-70% of the material for each class because I assumed that I didn’t forget the most recent material. This strategy worked well for me last year with 6 APs. I’d save full length practice tests for the weekends.