The LSAT is offered four times a year: June, September/October, December, and February. Do not take the LSAT until you have prepared for it! Your best strategy is to get prepared and take it only once.
The best times to take the LSAT are in June after your Junior year and in October of your Senior year.The June exam leaves you time for a retake in October if necessary. However, when you retake the LSAT most law schools will average your old and new scores together. It is a better strategy to spend enough time getting prepared the first time, then to take it before you are ready and plan to do a retake. The October exam date leaves plenty of time for preparation over the summer, and your scores will be reported well before admission decisions are made. The December date is too late for some law schools - especially if you are hoping for early admissions. The February date is entirely too late, unless you are trying to get a head start on the next year.