My best verbal advice?
SLOW DOWN. Reading everything once slowly is better than reading everything twice quickly
This is (deceptively) simple, but excellent advice. I'm a boxing fan, and one famous trainer - Teddy Atlas - often mentions that fighters must stay calm and relaxed in the ring. Why?
Because you can't do what you want to if you're not relaxed - if you're not in control. This applies to the GMAT as well. Read the GMAT Experience forums. People usually mess up at the very end when they realize that they need to answer ten questions in 20 minutes. The best way to keep everything under control is to take your time. That's not an open invitation to be excessively slow, mind you, but pace yourself. When you're comfortable, time yourself and see whether you can decrease the time a little bit each CR practice session.
Every time a CR or RC question appeared, I purposively looked away from the computer screen and took a deep breath. This gave my brain some much needed oxygen, relaxed me, and reminded me that I am in control.
Now, in terms of material, you still have time to read Powerscore CR
if you haven't done so already. For OG questions, read the answer and explanations completely, including the incorrect parts. In other words, don't just answer the question and check to see whether it was right. That's passive behavior. You want to be active and aggressive!
And I'm a firm believer in reading the passage first. Some people advocate reading the answer choices or question stem first, but that's just CR suicide. Not only can this distract you from fully absorbing the passage, it also wastes time because you will forget the question stem and answer choices by the time you have completed reading the passage. You will read them again and spend twice as much time on a question.
For RC, you don't have enough time to read a guidebook, so focus on practicing with as many RC questions as possible. Again, read the explanations fully. I also, and always, recommend LSAT RC questions to anyone who struggles with this area.
Sorry for the long post and lame boxing analogy.
GMAT Club Premium Membership - big benefits and savings