Does ISC get any easier??

I am currently almost through Unit 2 of ISC and let me just say, I am completely overwhelmed. All I have heard about this exam was how easy it was compared to others, however I find myself having more difficulty than I have ha with other exams like REG. I just don't see how it is possible to memorize all of this. I am reading the textbook, taking notes, watching videos, and it is still not clicking. I am starting to think I should have gone with TCP after a decent score on REG, but I decided on ISC since I took REG several months ago. Anyone out there have some positive words about ISC and maybe it gets better or any tips??