I don't know how much this will help, but here it goes:
Don't be discouraged. When I first took the SAT's, my scores were lower lol. But with a little practice, I found that its not impossible to score the iconic 'Ivy' level.
For me, the Math section was the most difficult; not much so because the material was hard, but because there were a lot of traps and misleading usage of words. I found it was vital to stay focused and take one step back before finally filling in that circle. Remember, each incorrect response - especially in Math - can result to a 40~50 point decrease in a high percentile.
I found there was no real constructive way to prepare for the Reading portion. The best way was to gather as many different sources of pratice tests, and try to grasp a sense of the 'SAT-esque' answers. It takes time and effort, but it was definitely worth it.
Finally, the Writing section - at least for me - was the simplest to prepare for since there was a constructive approach available: memorizing all the rules that appear on the SAT writing portion. Can't go wrong there.
I guess the most difficult part about the SAT is preparing for them all in the midst of excelling in school work, sports, and extracurriculars - especially if you want to apply to West Point. I remember when I received my set of worst scores, the sky suddenly turned yellow. Not only did I worry about my immediate scores, but I also had to dread the fact that I had to take them again and do better. I hope my tidbits can help you flush away any similar anxieties. Best of luck!