There are any number of reasons for a grad school applicant to switch gears from the GMAT to the GRE. The most common scenario though involves being unable to penetrate the 600+ or 700+ GMAT ceiling for an MBA application, usually because of the quantitative section, but not always, and that's ok! Some folks don't like cheese, others cannot dribble a basketball with both hands, so similarly the GMAT can just represent a seemingly immovable object for any one test takers and it would be silly to not seek an alternative way when a proverbial GMAT boulder lies in the middle of one path to graduate school.

So, now that you've made the decision to switch --> How do you make this change pay off with grad school glory?

Step 1: Take a Diagnostic GRE
The GRE, while similar in content to the GMAT is quite simply a different experience so you'll want to first head over to ets.org/gre/powerprep and take one of the two available free official online practice exams. Much like the GMAC, ETS (the GRE test maker) provides both free and paid practice exams using the exact same interface as its official test. Make sure you select PowerPrep Online Practice Test 1 and not the untimed version because that won't provide you a score for reference. Try to take your diagnostic in a single sitting under as similar to official testing conditions as possible, and yes that includes producing the two essays even though the free interface won't provide a score - shoot, I'll make an offer here and now that anyone who posts an essay as a reply to this thread will get a score from me - to guarantee that your diagnostic is as accurate as it can possibly be.

Once you've taken your diagnostic then take your scores to another webpage, ets.org/gre/institutions/about/mba/comparison_tool to gauge your performance for target business schools. Input your score results for the Quantitative and Verbal sections to determine how they would translate to a GMAT score. It's quite likely that your target business school will use this same tool to compare, so it's a great resource as you consider what GRE score an admissions department might be seeking. If you aren't using the GRE to apply to business school, you can ignore the GMAT conversion tool, but still research target scores at your desired programs to set a goal for your GRE journey.

Step 2: Get GRE-Specific Practice Resources
Much like the GMAT, you'll want to get the Official ETS SuperPower Pack for as many official practice sections as possible. The SuperPower pack provides a large overall Official Guide to the GRE and then two smaller textbooks or ebooks focusing on the Quantitative and Verbal sections. Use these for the most accurate practice drills available. However, you'll probably want to supplement your official ETS texts with third party resources, since the ETS simply does not produce nearly as many practice problems as the GMAC does for the GMAT. For those needing added problems, Manhattan Prep produces the aptly named 5 LBs of GRE Practice Problems that is probably the best bang for your practice buck, although GREPrepClub obviously has plenty of problems available too!

The good news though is that whatever math review content you have been using for the GMAT should be applicable to the GRE, too. So, there shouldn't be much need to get a GRE math specific resource, and in fact many of the available GRE math resources share content with their GMAT counterparts. Additionally, even though there is a second essay on the GRE, it remains the least important aspect of the exam for anyone who had previously been considering the GMAT for grad school admission. Just attempt the essays as part of your practice exams, the paid GRE PowerPrep Plus exams will even grade them for you, unlike the GMAT Prep software, and make sure you are scoring at least a 4 to consider this aspect of your application satisfied.

However, one new thing you will need to procure immediately is a vocabulary study resource. Whether in flashcard or app form, you will need to find a tool to build your vocabulary. This is the number one change from the GMAT to the GRE so take your time to research your favorite vocabulary tool. In a previous post we discussed GRE vocab study best practices, so check those out for more information on how to best prepare for this new need as a result of switching to the GRE.

Step 3: Set a Practice Test Schedule
There will be four more full online practice exams at ets.org/gre/powerprep after the diagnostic, one more free, and then three paid PowerPrep Plus tests, so you'll have plenty of online official practice GRE opportunities. Generally, you should plan on taking at least two more practice exams, with at least one reaching within 3-5 points of your score target before attempting the real test. Because the sections on the GRE are quite simply faster paced than their counterparts on the GMAT, the best way to get ready for that increased speed is to take as many practice sections and exams as possible.

There are obviously many more steps to ultimate GRE success, and for many GRE students additional help from either a tutor (such as yours truly) or an in-person or online test prep course can be helpful, but by taking these first three steps on your own you'll be setting yourself up for a seamless transition from the GMAT to the GRE!