First of all, your LSAT score is very important when it comes to applying to law schools. Everyone will have a different story about how it's weighted, and every school will look at them differently. But the fact is, those 4 hours could make or break you, depending on where you want to go to school. (Sorry if that sounds scary, but that's how it is! haha)
But... Practice, practice, practice!
In terms of how close your practice tests will be to how you actually do... that all depends. If you take a practice test, and then study for 6 months before the test, and then take another practice test, I'm sure your second score will be higher than the first and much closer to what your actual test score will be.
The fact is, the test isn't asking you factual questions... it's testing how you read, reason, analyze, and solve problems in a logical way. Because of that, I can pretty much guarantee that the practice tests you take aren't going to be a lot easier than the actual test. Essentially, your practice tests shortly before the actual test will give you a pretty good understanding of the range of where your final result will be.
And be prepared! And I don't mean with practicing... but before the test get a good night's sleep, eat breakfast and relax. The people that I talk to that do very well on the test are usually the ones who don't study for it at all the day beforehand (they've already had a year to study, I doubt another 8 hours will help). Go out with friends, read a book, watch a movie. Don't think about the test.
It's a lot of reading, a lot of thinking, and a lot of switching your mind from one thing to the next in a very short period of time. Don't freak out! :-D
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