A few weeks before the LSAT, many people find themselves on a plateau. They just can't seem to improve their scores. People find themselves on plateaus for many different reasons. One of those causes is lack of organization. Over time, when you've done quite a bit of studying for the test, you can start to get lazy with your process. If you're stuck on a plateau, one of the best things you can do is impose organization on your process, which can reduce your time per question and increase your accuracy.
Regardless of which section or question you're doing on the test, there's a process you can use to help yourself stay focused and work efficiently through the question. For example, in a Must Be True question the proper process is to first determine if any of the statements in the stimulus connect together across a common term. If they do, then the correct answer choice will likely test you on the inference possible from that combination of information. If not, then the correct answer will just be a restatement of a claim made in the stimulus. You then go through the answer choices, using our Contender and Loser system, looking for the choice that most closely matches your prephrase and getting rid of those answer choices that are not provable from the stimulus.
Each question in logical reasoning has a basic process similar to the one I just described for Must Be True questions. And each question type has additional efficiencies that you can take advantage of if you're aware of them. Again using Must Be True questions as an example, if the stimulus contains a single conditional statement, then dollars to donuts the correct answer choice will present the contrapositive of that relationship, and you'll likely find a Mistaken Reversal among the incorrect answer choices.
Now, you may be thinking that you don't have time to think about all of these steps and processes when you're taking the LSAT. I agree with you completely. You absolutely do not have time to think about those processes. Your preparation doesn't just stop at understanding that those techniques exist. You've got to drill them repeatedly until they become more or loss automated processes. That doesn't mean you don't actively apply them, it's just that they will no longer taking up as much of your active processing capacity.
And we've just discussed a process applicable to one kind of Logical Reasoning question. There are similar processes applicable to the Logic Games section and Reading Comprehension as well.
Part of this is not new. I'm sure you know that there are defined ways to approach the various questions. But are you actually applying them? If not, you need to start refocusing on process right now. You've got to take an inventory of the processes you know and compare them to the processes you are actually using. If in conducting this survey you find that there are question types or game types for which you don't even know what process to use, you need to fill that gap in knowledge.
Then, as you review your practice tests and reverse engineer the questions, include the processes in your review. For a particular question ask yourself how well you did at applying the process. Figure out how you could have been more methodical in your approach and make notes about your results. From each practice test pick a few areas that seem to need the most work and retrain those processes. After a while, you'll become more aware of when to apply the processes and how to do so efficiently, and you'll find that you're making fewer of those "dumb mistakes" that you probably bemoan after each practice test.
Processes and methods are not your enemy, and they are not barriers to speed on the LSAT. Failure to use the right procedures at the right time, and failure to drill the procedures continually until they are second nature will cause you to remain stuck on the plateau you're hating right now. But you can make the choice to focus on process, assess your performance, document your results, train up your weak spots, and attack the questions more efficiently the next time out. The test changes very little over time. So, if you're not making the improvements you want you can't just sit there and hope that something will change. You've got to make the choice to change your approach to your test preparation. It's all on you. The good news? You can do it.