Personally, I went through 5-6 book's critical reading sections (Kaplan, BB,
PR,McgrawHill, Silverturtle and one or two more)...I started as a 590 and now im scoring around 730. You must know vocab (try getting
PR flashcards) and direct hits. I just kept studying..improved to a 670ish by the book knowledge....then suddenly I just hit a breakthrough and started getting 700-730s nonstop