i must object to the content of the preceding two posts, which basically seem to say that the OP should rush through the official guide as quickly as possible, just solving problem after problem after problem.

this is not the way to study, especially for quant. you've got to remember that, during study, solving problems is not the point. because you're not going to see those problems again, they're only valuable inasmuch as they let you derive takeaways that you can then apply to other problems on the test.

see this post for the general idea:
https://www.beatthegmat.com/depressed-th ... html#62498
that post also contains numerous other study hints, too, but you should especially concentrate on the part about takeaways.

for a more concrete example of what i mean, check out the following thread. it's a bit extreme - i derived 5 different takeaways from the same problem - but you'll get the point. notice that all of the takeaways are general lessons, which could then be turned around and applied to other problems.
https://www.beatthegmat.com/gmat-prep-ge ... html#80697

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in any case, if you're studying problems COMPLETELY - which means (a) deriving takeaways, (b) taking inventory of any strategies you used and/or mistakes you made, AND (c) briefly considering other approaches to the problem, then it should take you at least a month or two to get through the official guide (depending on the level you're currently at). if you're getting through the entire OG in a week, then either you're a genius or you're not penetrating thoroughly enough into the analysis of the problems.