WIth any study plan, you need a structure. First determine when you're taking the test - schedule about 1-2 months of preparation.
If you're following the GMATPill
Study Plan for 30 days, then give yourself about 1 month to prepare. Then follow the plan to prepare in that one month - OR develop your own 1 month study strategy.
Typically, most people will say:
1) Take GMATPrep diagnostic practice test (there are 2)
2) Buy Official Guide 12th
edition questions (13th edition will be coming out April-May timeframe of this year)
3) Practice or follow a GMAT Prep program for guidance on how to practice effectively, approach questions with an attack strategy, and score above your high range that you got on the diagnostic tests. They vary based on textbook vs classroom vs online video. We feel that online video (specifically conveying thought process) is the best way but everyone's learning strategy is different, so go ahead and do your research and figure out if there's a program out there for you.
Lastly on test day, focus on psychology, confidence, and mental preparation. Use tricks to improve reading speed and focus, don't be reading EVERY word, and be able to spot traps within milliseconds. These little things will help you improve on test day.
Best of luck.
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What's Inside GMAT Pill?
Zeke Lee, GMAT Pill Study Method (Study Less. Score More.)
GMAT Pill Reviews | GMAT PILL Free Practice Test