If you’ve made it to college, you have done this part before.
We all learn differently, and I’m not going to diagnose what is the best tactic for you. What I will do is share some general guidelines about efficient learners.
Simple memorization is limited by the volume of information you can hold in your head. You need to reduce the syllabus in to something that will fit in your head. You reduce the syllabus by ignoring what you don’t think will be tested as thoroughly (this much more important on the EA and Fellowship Exams than the preliminaries) and creating a system in your head that unpacks complicated ideas from a few memorized starting point. People who learn quickly and permanently create a map in their head of the main ideas and patterns of the information, and can fill in the details at will.
Ignoring syllabus items is risky, but some people have a knack for it. As you do practice problems, you can identify what kinds of questions can be asked about what what subjects. Some subjects are so complex that the only questions that can be asked have a big complicated set up and an easy to guess answer.
As for memory unpacking systems, acronyms and memory palaces are examples. You have to find what works.
On Putting the Time in
Do it. The amount you learn is not linear with respect to time. It compounds. The time you spend with 4 months until the exam lays the foundation for efficient cramming right be fore the exam.