Good job getting a 720 on your first practice exam. I'm surprised that you've only taken a single practice exam - I usually recommend that my students take at least 4 practice exams before taking the actual GMAT.
For timing, have you tried using benchmark times to keep track of your progress? It's a simple exercise of calculating which question you should be on at regular intervals throughout the exam.
Here is an example for Quant (the same can be done for Verbal):
75 Mins 1
65 Mins 6
55 Mins 11
5 Mins 36
You should create these timing charts and practice with them on your practice exams. During the "Instructions" (which you shouldn't need because you know how to take the GMAT) use the time to write out the timing chart on the provided notebook. You may want to write the chart in a few locations in the notebook so you don't have to waste time looking for it. As you hit the benchmark times, compare your current progress with your benchmarks to see if you need to speed up, slow down or maintain. If you are tracking your timing throughout, you won't find yourself rushing at the end.
As for stamina, my best advice is to take multiple practice exams and get the most out of your breaks. It sounds like you don't have a lot of time before you take the exam, but you should take another practice or two so you can get more comfortable performing at a very high level for a long period of time. The breaks are absolutely critical to help your mind stay fresh. You need to break away from the exam completely (don't think about questions you may have missed in the previous section). Eat a snack, drink something, do something physical to get your blood pumping, splash some water on your face...whatever it takes to recharge your brain quickly. Also realize that due to testing center security protocols the real time of your break will be much less than 8 minutes.
You may have already scheduled your exam. If so, good luck. You are in a pretty good position. I usually recommend that people score be scoring above their target score in practice before taking the exam. If you don't hit your target on the first try, don't worry because many students take multiple exams before reaching their goal score. The GMAT requires you to space your exams 31 days apart (so you won't have the chance of seeing the same questions), so keep that in mind for your schedule.
Kyle Widdison | Manhattan GMAT Instructor | Utah
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