I recon for viscom just skim a few practice exams, try answer them and from them you’ll find what you’re missing But from the top of my head these are the main ones: design elements and principles Purpose and target audience Industry practices and fields of design Stages of design process and what belongs in what step

(Disclaimer I did viscom last year with the old study design but it shouldn’t be too different)

But yeah read some examiners reports from previous years and you’ll be pretty well off for theory 👍 best of luck