Hey kayr2020,
I would recommend starting with one of the Pearson practice tests to get a feel for how the exam works. This will let you know which areas you need to focus on and which ones you already know well. After you finish one Pearson test, study the areas you're weak in using your other materials. Then, when you're finished studying those areas, you can take another practice test and repeat the process.
I suggest starting with the Pearson test because I did not, and I feel I may have wasted some of my time because of this. I was worried about my chemistry score because I had not taken chemistry in 2 years, so I spent about a month studying just chemistry. When I finally took my first Pearson practice test I did fine on the chemistry, but I realized I had spent time studying a lot of concepts that were never asked on the actual test. I could have devoted my time to studying other areas that I was weaker in. I think taking a practice test first would have helped me better focus my studying.
For my credibility, I recently took the PCAT in July 2014 and did well (92% composite for my preliminary scores). However, I did not use Dr. Collins and Kaplan to study, only the 3 Pearson tests and various textbooks I already owned from college.