There are a number of opinions on when to take your first simulated test.
here is what I did and it seemed to work, but this is definitely not the only way:
I took a practice test (PowerPrep or GMATPrep) - yes I "wasted" it but I was able to get my position at the beginning of the prep. Having a starting point, and a goal, I was able to put together a strategy/study plan to achieve my goal. Keep in mind that i scored 540 on my powerprep, so I definitely needed a lot of help. I thought that was a better strategy than assume I was good in something, which I was not and then I used my weaknesses to improve. It gave me a realistic picture and a necessary motivation to kick my behind. On the other hand, you could also take any similar CAT test and get a clear picture and save your GMAT Prep for the last month to hone your strategy and evaluate final result with close accuracy - any GMAT book you buy these days has a test in it.
Another strategy is to take a GMAT Prep test in the middle of your prep - take the verbal portion only for example after you are done with verbal to get an understanding of your position - I think that's also extremely helpful too but any practice test from Kaplan
, PR, or MGMAT could do that for you. Of course GMAT Prep would give the most accurate results.
P.S. Official Guide is not very hard by the way, so don't be fooled.
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