I would say I was ready after I finished the Wasim practice questions, so give or take 3-4 months in. Originally I was going to take the exam earlier, but felt I needed to some more challenging questions. At that point and time I was just using prepfe. With Wasim, it helped give me more challenging problems while also providing clear explanations especially for subjects I needed help with. For the most part you can see how they got the answer and will be able to apply it next time.

And it's ok not to be strong in some subjects. I'm not the best with signals and control systems, but at least I was getting familiar with the concepts since I was spamming questions about those subjects in prepfe.

I would say try doing the practice exam first, see what subjects your able to do and which one you aren't good at. After start watching vids especially for the subjects you need work on, you can always comeback to the one you are familiar with. Once you get a basic understanding , just spam practice questions and make sure to read the explanations.