Use TTP!

Target Test Prep's self-guided review course is, in my opinion, the single most important test prep resource grad school candidates can use. Chapter-by-chapter and module-by-module, Target Test Prep (TTP) covers, in detail, each concept candidates will need to understand to score highly on their GRE.
Pros: Affordable, self-guided, very large question bank for practice, explanations for how to complete problems, built-in error tracking, calendar feature to create a study plan and track progress
Areas of improvement: High number of quizzes at the end of most chapters were time consuming, expand the verbal question bank, provide more video walkthroughs of solving problems