What should I do to improve on SAT Chemistry?

<p>Hi everybody~
So, I will become a senior this year and I will be taking the SAT Chem test this upcoming October, but I'm a little worried.
I took Honors Chemistry my sophomore year and I even took the SAT Chem test in June two years ago, but I did embarrassingly bad (probably because my chem teacher left on maternity leave halfway through the year and we got a horrible replacement, I got a 600 in case you were wondering).
I didn't take AP Chemistry my junior year and instead, I will be taking AP Chem my senior year and here's my concern: I haven't done chemistry in an entire year and I have forgotten most of it already.
So over the summer, I've been reviewing my old Barron's Chemistry book from sophomore year and I've been taking notes on each chapter. I've also been taking practice tests from multiple books such as the Kaplan's, Princeton Review, and the Barron's, and my score tends to fluctuate from 650 to 720.
My goal is to get a 780+ on the upcoming SAT Chem test in October, and I feel like I haven't been improving much with my practice tests. So I was wondering if you guys have any advice for studying SAT Chem in a more efficient way?</p>

<p>Sorry, I just realized this is a really long wall of text, so for those who tl;dr, do you guys have any helpful tips on studying SAT Chem and what's worked for you?</p>

<p>Thank you! :)</p>

<p>Since I bought McGraw Hill’s Chem and wrote all topic’s summary, I raised my score 630 to 770. Also, you can use the SparkNotes.</p>