SAT preparation requires that you immerse yourself in SAT questions and review material. Start off your prep by getting the proper study materials. There are alot of SAT books out there, many of which are inefficient, inappropriate, and/or boring. Here are some of the best SAT prep books - buy them now and start studying immediately!
The Official SAT Study Guide, 2nd edition is published by the company that makes the real SAT, so it contains the MOST ACCURATE questions of all of the SAT books on the market. You can not properly study for the test without this book. Buy it now and work on as many questions as you possibly can.
The "strategies" and "review" sections of the official guide are not the best or most interesting, so if you need this type of material, try out Cracking the SAT, 2012 Edition (College Test Preparation) .
If you need to increase your reading score significantly, you must learn appropriate vocabulary, so try out these lighthearted and easy books: Illustrated Word Smart: A Visual Vocabulary Builder (Smart Guides) and More Illustrated Word Smart (Smart Guides).
Now that you've got your materials, here are some essential SAT strategies to memorize and use: 12 Essential SAT Strategies - General