I'll give you the not-good news first. There's not a lot I can do to help you improve 50+ points in 8 days (now only 5 days, actually).
In general, people should expect to score on the real test what they score on a practice test about a week before, assuming that the practice test was taken under 100% official conditions. (If the test was not taken under 100% official conditions, then your score may be inflated.)
First, did you take the test under 100% official conditions, including the essays, the length of the breaks, etc? If you did not, tell us exactly how you deviated from official conditions.
Best-case scenario here is that you did take it under 100% official conditions, in which case we're looking at a 50-point deficit. Most people would not be able to from 650 to 700 in a week. You have three options:
(1) Take the test anyway and either lower your goal score or just hope you get lucky (though the odds are pretty long).
(2) Take the test anyway in order to get the practice, but plan to take it again in a month or so, and don't expect the 700 this time.
(3) Postpone the test.
If you choose to take the test in 5 days, read these two articles and follow the advice (though don't do it all - the articles are for the final 2 weeks and you have only 5 days left).
http://www.beatthegmat.com/mba/2010/08/ ... -game-planhttp://www.beatthegmat.com/mba/2010/08/ ... -to-reviewIf you choose to postpone, then use the following article to analyze your most recent practice test (ideally MGMAT). If you deviated greatly from official conditions (including skipping the essays!), then take another practice test under 100% official conditions and use that to conduct the analysis. Then come back here to post your analysis (not the raw data itself - your analysis of the data) and we'll help you figure out what to do to improve.
http://www.manhattangmat.com/articles/e ... -part1.cfmGood luck - let us know what you decide.