Retake gmat - tips/ study plan (need to improve verbal)

Hi,

I got 600 in gmat (Q 48 and verbal 26) I'm happy with my quants but very disappointed with verbal. I got higner in verbal in my practice tests (but not much better around 35). I wasn't able to complete the verbal section and randomly clicked the last 5 questions. I am planning on taking the gmat again and wanted some advice on how to improve my verbal score.

I used the MGMAT sentence correction and CR books. I also did the problems form OG guide and supplemental guide once. When i did them, i didn't time myself. I did get 80% of the CR and RD correct without timimg.

Please advice on a study plan. How many weeks? what shld I focus on?. To begin with I spent a lot of my time on math and much less on verbal. I want to retake soon so I don't forget the stuff in math.