10% Improvement in 4 weeks?

Hello, world. I need a bit of help - I have not yet scheduled the GMAT but I am planning to take it in the next 4-6 weeks (so I have a month for essays and to apply for 2017 by end of round 2). Currently, I am hovering in the 660 range (Q44, V37) with a target score of 720. I only tried IR once with...