The use of audience-centered visuals is one of the four essential focus in technical communication.
THE IMPORTANCE OF USING AUDIENCE-CENTERED VISUALS
Visuals are important in print or digital documents in oral presentations, and in multimedia programs for several reasons; they help readers understand and remember complex information they show how work and they show how items are organized or actions are performed.
Because they focus and organize difficult information into more simplified form, some of benefits visuals make data easier for readers to understand and remember. Visuals work because readers want more than just raw information; they want the information provided so they can understand it through a glance.
WHEN TO USE VISUALS
Visuals should be used to enhance and your document There may also be organizational reasons for using visuals as clarification of difficult information and some of information the can abbreviation through visuals 
Often the most effective and supportive means are visual images, visual images are an excellent means of support, but do not replace the underlying discussion in the actual text. Commonly used charts include flowcharts, pie charts, and organizational charts. Pie charts using colors in visualizations
Color focuses reader attention and helps readers identify various elements of a visual. Most of the software you will use to create visuals (e.g., Excel, PowerPoint) automatically adds color to charts and graphs.