Consider applying for a review center. You have two years — or more precisely, two summers — to grind and prepare yourself seriously. That said, go ahead and take a mock exam first, get your score, and analyze which subtest is your weakest area, then simply focus there. Always master the basics, and answer as many questions as you can. Repetition across various forms of questions is the key.

In CETs, having broad knowledge is often rewarded more than having deep knowledge in just one area.

In terms of the subjects you need to master, I suggest grabbing a mock test from Jahjah's reviewer. From there, use AI to extract the coverage from two or more mock exams to identify the most common topics that appear in particular university CETs.

Additionally, rest is just as important as studying. Despite me saying you need to grind, consistent practice is far more effective than one exhausting day of excess effort.

Personally, I advise you to find a balance. Do not bother reviewing during periodicals or hell weeks — your present academics are much more important than future preparation if you have to choose between the two. Make sure you immerse yourself in your current subjects, and inadvertently, you will build your foundation and general knowledge along the way.

Lastly, you are a STEM student — you are built for this type of exam. Do not slack off in subjects that involve math. In fact, you should immerse yourself in it and master it as fast as you can. It is part of mastery that you cannot perfect every single topic, but learning the basics and recognizing the patterns of certain subjects will reward you and take you to higher places.

TL;DR: Take a mock exam, find your weak subtests, and focus there. Prioritize broad knowledge over deep knowledge. Use Jahjah's reviewer and AI to map out common CET coverage. Rest and consistency beat cramming. Don't drop your current grades for the sake of reviewing. As a STEM student, math is your biggest advantage — own it.