When should I start studying for the LSAT?

In addition to knowing the application deadlines for the law schools to which you are applying, consider whether you will be taking a prep course, and ensure you have enough lead time for that. They have different schedules depending on your circumstances (e.g., some people have jobs in addition to school and can only study on weekends, etc.). Although it has been many years since I took the LSAT (and I don't know all the rules for retaking the exam), you may want to take it earlier than you might otherwise, in the event you don't do as well as hoped and need to retake it. Not to be pessimistic, but you don't want to lose the opportunity to take it again if you don't get the score you are shooting for the first time! Best of luck, and remember that, with practice, you can greatly improve your LSAT scores, so plan accordingly and you'll do great.

Let's consider the date from the end time point, the application deadline for a law school. Assume you plan to enter a law school in Sep just after your graduation from a college, you need to submit your application in the first semester of the fourth year. Considering one or two months for preparing application package, you may want to get your LSAT score at the beginning of your fourth year. Therefore, "after the second year" to begin your LSAT preparation is sound.

That depends. When do you want to start law school? If you're going straight from college to law school, then you might take the test late junior year. That way, you'll have time to take it again early senior year if you want a better score.

Under that timeline, the test is about 9-12 months away. Take some practice sections. Get a sense of what score you want, and where you currently are. Broadly, how you feel about the material. How hard will it be for you to "learn the test"? If you feel confident, you can probably afford to wait a few months, if there are other things you'd prefer to be doing. But don't worry if the test feels challenging. Make a plan to improve, and see it through to the test date.

Good luck!

I wouldn't start studying too early. You want to focus your energy on getting good grades too, because that is something that law schools also care about. I studied for the LSAT in my sophomore year of summer and found it a bit too overwhelming, didn't do as much prep work as I would have liked, and then ended up having to redo everything again in my junior summer.

Also, I suggest if you can, to take a course instead of self-studying. Look up reputed companies near you and actually take a course. The course will be designed to help you "peak" during the actual exam. This is similar to the U.S. bar exam, where most bar courses are 2.5-3 months long and set you up to have the knowledge to pass. Test-taking for the LSAT is a skill and you can lose it over time, which is why you want to perform when you feel the most optimal.

Source: took LSAT and went to law school in the U.S.

PS - Some U.S. schools are now allowing the GRE for admissions.