"Visual design, like anything is governed by rules. Here the principles that visual designers use to manage media:
hierarchy
focus
clarity
balance
Hierarchy is a series of ordered groupings of people or things within a system. It is everywhere in our world. Things are grouped by class, size, and authority. Grouping things makes it easier for us to understand the world around us.
This same idea carries over into visual design. In fact, it is actually the main principle of visual design. The main goal of the elements of design is to create a strong and consistent hierarchy. Hierarchy is the strategy for achieving all other principles of design: focus, balance, and clarity.
Designers visually group all the parts of an ad using the elements of design:
color
size
line
shape
texture
It's important that these elements of design are used to present the information logically and predictably. This way, readers can scan the ad and quickly and easily pick out important pieces.
Readers first see pages or billboards or computer screens as large masses of shape and color on a contrasting background. Next, they begin to pick out specific information, like images or symbols. Finally, they tackle text and begin to take a look and individual words and phrases.
Keeping this process in mind, the ad designer has to create a hierarchy within the lay-out. He has to group things in the visual order that a reader naturally uses to process them. Take a look at the figure below."

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