Some CDers complain that they hit a wall while trying to improve their critical reasoning skills. Usually they claim that there is hardly any sign which indicates an increase in their accuracy rate for CR questions. If so, you need an appraisal explained below:


1) What are the reasons which cause you made the wrong choice? Are you missing the questions because you misunderstood the question or did not know the questions type? If the former is true, then you need to improve your reading comprehension skills. If the latter is true, you should choose a prep book or course to get a good handle on questions types. Study to the point that you 1) know all the question types (there are not too many to begin with), 2) can identify the question type by reading the question stem, and 3) can get most if not all questions right when you are not timed.

2) Run drills using authentic test questions/sections. Now it's time to practice CR sections, and to make full use of you time, you might want to consider the following steps:

a) Read the stimulus first. Quite a few gurus, such as Kaplan, advocate reading the question stem first. While it might be essential to know the question types thoroughly (it changes the way you try to find the answer), reading the stimulus first was more beneficial for a number of reasons, not least of which is that almost all the questions require you to fully comprehend the passage at hand. Therefore, if you don't have the added pressure of looking for some unknown things (meaning the potential answer) other than the argument itself, you could read the stimulus faster and more accurately.Focus on the argument!

b) Recognize patterns and components of the argument in the stimulus. Recognize when an argument is flawed and why it's flawed immediately. Recognize assumptions. Recognize conclusions as opposed to sets of facts. The GMAT basically reuses a lot of ideas. Correlation vs. Causation. Member vs. Group. Sufficient vs. Necessary. Number vs. Percentage. Once your brain and eyes are trained to dissect the argument into functional parts, you would quickly find out what is right or wrong about this argument, then proceed to the 5 answer choices for the correct answer. In the end, it is purely mechanical.

c) Set timing goals. Try to do ten CR questions in 20 mins. Then shorten the time to 15 mins. Then to 12 mins. 

3) Finally, as always, review your wrong answer choices, and know why they were wrong and what caused you to pick them. The worst dream for a test taker is to repeat the same old mistakes over and over. 

There is really not much more to it beyond the above. Practice will make you quicker, but don't practice for speed unless your accuracy is high. Also, make sure you are mentally strong and confident. Do not worry too much about your accuracy rate while practicing. Do not practice when you are tired. Get sleep, get nutrition, and do not start an argument with your significant other before you practice!