Bad score on practice tests

I am planning to take the gre exam in another 15 days .As i gave the quantitative test on Power prep and scored 580.
which i belive is a bad score
Is there any way i can improve my score.

As far as QA goes what i will suggest is take the entire 45 mins whilw answering i can assure u that foes a long wa in improving your scores. Concenrateo nt he firest few answeres u give the Friest 10 that affects your score the most.try and get all right inthe first 10. Above all be calm coz th Math is very general as far as GRE thing goes so dont wory VA needs so me time so do take care of that.
All the BESt and do post you score after your test.