Vocabulary knowledge will play a big roll in your success. Try to learn the roots of words and the meaning of prefixes and suffixes to help you guess when you don't know the meaning of the words. You can find lists of SAT-specific vocabulary online or in your study books. Flash cards can go a long way in helping you to learn vocabulary. Write a word on one side and the definition on the other. You can punch a hole in the corner and use a metal ring to keep them all together. Review your SAT vocabulary words whenever you have free time.
Familiarity with the test format can go a long way in improving your score. When you don't have to read the directions, you have more time to answer the questions. Look for practice tests that are from real SAT tests. Some practice books don't include real test questions--only questions that they've designed to be similar to SAT questions.
For at-home study, books can help you to learn more about what to expect on the test and how to prepare. SAT study guides can be particularly helpful in teaching you how to solve math questions because they'll include a detailed explanation of how to get the right answers. Visit a book store so that you can browse the many available SAT study guides to find one that will work best for you.
Though they can cost more money than the other options, SAT prep courses can really help you go far. You can attend group classes in your area or hire a one-on-one tutor to help you with your specific challenges. Look for a course that teaches you test-taking strategies in addition to prepping you for the SAT. Some people have a hard time taking tests, which can hurt their score.