A 130-point increase in 3 weeks is a TALL order. You may need to consider rescheduling.

To increase your score, it's important that you identify your areas of weakness. A good way to do this is to take full-length practice tests and then analyze them. During this analysis, there are four main areas of weakness you should watch for:
1. specific Quant skills/concepts (e.g., algebra, standard deviation, etc.)
2. specific Verbal skills/concepts (e.g., verb tenses, assumption CR questions, etc.)
3. test-taking skills (time management, endurance, etc.)
4. silly mistakes

For the two weaknesses, the fix is pretty straightforward. Learn the concept/skill and find some practice questions to strengthen that weakness. To focus on one topic at a time, you can use BTG's tagging feature to isolate one concept. For example, here are all of the questions tagged as statistics questions: https://www.beatthegmat.com/forums/tags/ ... statistics
See the left side of that linked page for more tag options.

If your test-taking skills are holding you back, then you need to work on these. For example, we have a free GMAT time management video at https://www.gmatprepnow.com/module/gener ... es?id=1244. Then you should hone your test-taking skills by taking more practice tests.

Finally, if silly mistakes are hurting your score, then it's important that you identify and categorize these mistakes during your prep so that, during tests, you can easily spot situations in which you're prone to making errors. I write about this and other strategies in the following article for BTG: https://www.beatthegmat.com/mba/2012/09/ ... n-the-gmat

Cheers,
Brent