I literally just published a new series about exactly this! See here:
http://www.beatthegmat.com/mba/2016/08/ ... study-planTake a look through that and then let me know any questions about any of the steps. (It's long. Try to concentrate on just one step at a time.
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I'll add two things:
If your current scoring level is 450, then you will need to start with Foundations of Math and Foundations of Verbal. Did you buy those strategy guides as well? Not sure whether you got the complete set or just the 10-set.
Given that you're working full-time in a demanding job, you'll probably need more than the average time. I'd aim for a 4 to 6 month timeframe instead of the more common 3 to 5 months.