hi manray, congrats on the 580~ you're already above national average.
Despite the fact that you finished early on the verbal section, it is your weakness right now. I'd focus on taking a couple of practice tests (GMATPrep, MGMAT, Princeton Review
, Knewon, etc.) and see how you're doing in verbal. What type of questions are you getting wrong? Most people suggest Manhattan GMAT Sentence Correction
for quick and easy SC fix. Reading Comp is probably the hardest to improve on as you'll find that you can't really develop good reading skills in just a month or two. Critical reasoning is practice and practice. Before you know it, you'll find a pattern of critical reasoning and be able to guess your answer. Manhattan GMAT
also has some good books on the quant section, though I haven't used them before (read about them on this forum). Depending on what your target score/schools are, you can work out a schedule to better prepare you for this second time. Also, if you haven't, definitely get the Offcial Guide as it contains the most accurate questions to what you'd see on the GMAT. Best of luck!