I would first narrow down the areas in which I have least accuracy and then take up a high school or any maths book and review those. The quant review section in Kaplan
book is good, but brief. I personally find DS based on number properties to the hardest since there are so many values the numbers can take. Ratio/Percentage/Geometry/Algebra are usually easier since there you can go wrong in fewer ways. So review your mitakes, see which area would give you the most return for your time. Also, when you look at any formulas in a review section, try to derive those rather than just try to remember. It would give you a better understanding of underlying concepts.
Hope this helps.