Categorisation is a key skill for presentation designers. Raw material usually consists of lists of bullet points: some are detailed, some are generic, some are important, others not, some overlap, sometimes lists are not complete.
Moving around these points, grouping, categorising them is an important part in the design process. Next is the decision what issues to tackle on what slides. Where can you condense, where do you need to break things up over multiple visuals.
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