You’re set on attending law school next fall, but you have yet to take the LSAT, and that gives you a choice: should you take the December exam or should you take the February exam? Consider your decision carefully, before you decide, for it is no matter of indifference.
Generally, taking the December exam would be better: your test score would be received, along with your application, at a time when law schools have fewer seats filled: you will have less competition and more of a chance to secure your spot. In any case, check to find out when your desired school accepts applications and test scores. Taking the exam in the spring not only gives the impression that you put off studying for the test, but some schools don’t accept applications as late as March, when the exam scores are returned.
Nevertheless, that does not mean you should automatically intend to take the December exam. How are your practice exam scores? Take a few practice exams, and try to set up realistic testing conditions. If you are scoring within ten points of your target score, then never mind your nervousness: take the exam in December. If, however, you are scoring below ten points of your target score, then you should consider waiting till February.
In the interim, you might hire a tutor to help bolster your score, and meanwhile take as many practice exams as you can. This is better than doing poorly on the exam, as you can only take it three times per two year period.
So plan it out, and good luck!