Many students expect that taking a summer off will provide sufficient time, giving about 2 to 3 months to prepare. Other students expect they’ll be able to prepare sufficiently in less time. Realistically, given the volume of material on the exam, it helps to prepare as early as possible but to reserve a significant amount of time in the 1 to 2 months immediately before the exam to do intense review.
Ideally, all pre-requisite courses that cover MCAT material have been completed before or during the preparations for writing the MCAT. Generally, one’s third year of undergraduate study is a good time to consider writing the exam. By that time, students have typically cleared all of the pre-requisites and may have gained in maturity and discipline from when they started university.
A typical study schedule for the MCAT might plan on using the summer to study heavily for the exam and then writing in August. It would then help to begin by doing some very light studying for the exam in the Fall or Spring before that summer (with this being a priority that is secondary to your full-time studies). In the summer, the eight weeks prior to the exam can be used to do an in-depth full-time study for the MCAT. The first half of the time might be spent doing a comprehensive review, with the final weeks being spent doing practice exams and practice questions in areas of weakness. Ultimately, there a lot of ways to study well for the MCAT. Furthermore, people tend to be fairly particular about how they prefer to study, so listen to your instincts about what works best for you. This advice also applies to the usefulness of MCAT courses. Self-directed learners may not find them useful at all, whereas some people excel in a classroom environment.