Word list groupings

[Gmm21]

I have been studying since May mostly out of Princeton review. I have just been making a ton of notecards and memorizing words and trying to increase my usage of them. I recently bought the Kaplan verbal book and they have a section on grouping words. Does anyone have any good strategies on studying this way? How to go about studying using the grouping way. I took the test in July and only got a 480 on Verbal and I need around a 650. I take the test again August 21st. Any help is appreciated thanks!