I started following this religiously for recurring decks, and the results have been outstanding.

If you want to hone your communication skills in general:

* Do not add animations * Do not use themes * Force every bullet point to fit on a single line * Points need not be grammatically complete * Use a font size that you can read from more than nine feet away * Talk about - don't read from - the slide

And now, some unconventional advice:

PowerPoint can absolutely replace Vizio, and you should disregard all the rules when you create product announcement decks where style can trump substance. Some of those slides have over a hundred animations and must be split up into three or more pseudo-slides (initial state, N keyframe slides, final state) seamlessly.

PowerPoint is an extremely versatile tool, and its success and failure modes directly mirror the user's.