What notes should you keep while preparing and how to do so effectively?
If someone offers you a great summary of all formulas, tips and tricks for GRE - decline it. In order to be engaged in learning (as studying must be an active process), I advise you to take your own notes. Add examples where needed to clarify things you figured out along the way. Moreover, different students need to practice different questions and relate to different notes according to their own performance. Thus, there's no "one size fits all" material, but rather what YOU need, according to your own level of performance, strengths and weaknesses.
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