This article on designing with eye tracking in mind from InVision does a great job of breaking down tricks for leading your audience/reader through a document.
Professional graphic designers are trained to understand and design with eye tracking in mind (from what I've read), but there are tricks anyone developing visualizations or communications content can use.
For example: give more thought to selection and placement of photos. If your subject is looking at the text you've included, your reader will naturally follow their line of sight (as you can see in this heatmap tracking where the reader is looking).
The examples they give demonstrate the power of preattentive processing (what you see and process without even thinking about it), emphasizing how preattentive attributes like color and size help you manipulate your reader to focus on your key points, which we routinely use to develop great visualizations.