Hey africanpharmd14,
The chemistry and math sections were the hardest for me, too. When I first started studying, I was overwhelmed and didn't know where to start. What helped me tremendously was using the 3 Pearson practice tests which were very similar to the actual exam I took. I took one test early on, and this helped me identify what types of questions they would be asking and what concepts I needed to review. This was useful because before taking the practice test I was just going through chemistry textbooks and studying everything I saw. This was a waste of time because I often studied concepts that never appeared on the PCAT. After using the Pearson practice tests, I could identify which topics they were most likely to ask about and study those in depth. This strategy got me a 93 for the chemistry section on my July 2014 PCAT, which was great for me because I did horribly in gen chem and organic in college (mostly Cs). Also, I don't know if this is true for future tests, but for my test there were several passage-based questions in the chemistry section. I read that these were experimental and did not count towards my grade, so I skipped them and did them last. I think this helped me out a little because I had more time to focus on the questions that actually mattered. For more specific advice, I would suggest knowing the structures of all the amino acids. Every practice test I took asked at least one question about amino acid structure, so if you know those really well then that's one free point right off the bat. You should also review nomenclature and how to determine which compound has the highest/lowest boiling point by looking at its structure. You should also be very comfortable with converting between moles and grams quickly (it's a good idea to round and use simple numbers to save time) as they ask many questions that require you to do conversions.
Math was my worst section (72), mainly due to the time constraint. When I first started studying the math section, I got between a 10-20% on the Pearson practice test QA section, which horrified me. What helped me improve my score was just going through and doing all the easy ones first. If a question had a block of text I had to read before answering the question, I would just flag it and come back to it later. This gave me more time to work through the simpler problems with just equations. Using this strategy and studying the questions I didn't know how to do helped me improve my score from a potential 10-20% to a 72%, so I was pleased with the outcome. It's frustrating because I know I could have done better with more time, but it is what it is.
Even with my poor QA score, I ended up with a 92 composite score on my preliminary report. Again, I highly recommend the Pearson practice tests. These were the main tools I used for studying and I think they are the reason I did well. I hope this helps; best of luck studying!