Hi Sarah,
Don't panic! Your writing sample isn't that big of a deal, and you don't need much time to prepare. So, it will be ok
First, the one thing you need to do is become familiar with the format of the Writing Sample. Here's the basic overview of the sample, along with two prompts:
http://www.lsac.org/jd/lsat/prep/writing-sample.
Very briefly, they give you a situation, and then two possible solutions. You have to write an argument in defense of one of the solutions. The good news is that there are no wrong answers! Both options will have pros and cons, and either option can be defended successfully.
The key is to keep it simple and to write clearly and persuasively. You don't want mistakes or bad grammar. We typically suggest that you first state your choice, then talk about the strengths of your option, while downplaying the strengths of the choice you didn't select. Then talk about some of the weaknesses of your option (because they all have them, so you don't want to ignore them). Show that you recognize those weaknesses, but that you didn't feel they were significant enough to stop you from making this selection.
All in all, it's pretty simple, and the law schools know that you are writing about a topic you don't care about after taking a grueling 3+ hour test. And they already have a better example of your writing in your personal statement, so the Writing Sample is given very little weight in the process. Note: this is less so if you are an international student. In those cases, they do tend to look at those samples because they want to see the quality of your writing when there are no editors around.
Please let me know if that helps. Thanks!
