For my verbal prep I used ManhattanGMAT Sentence Correction guide, The Official Guide, and gmatfix verbal flashcards.
1) If you don't already have it, consider getting the ManhattanGMAT SC guide and go through its lessons.
2) Get the gmatfix verbal flashcards (you can evaluate some for free); these cards are broken down into SC subtopics, with each topic giving you loads of examples and pinpointed lessons on how the topic is tested on the GMAT
3) Once you can go through the flashcards for a particular topic without error, use the Manhattan guide to find the specific questions in the OG that test the topic you're studying. Practice those questions and study the explanations carefully.
This is just a snippet; you can see my full debrief at
www.tinyurl.com/gmatpost where I point out what worked from what didn't work for me.
Best of luck
