When we set out to design a piece, after understanding its purpose and the intended audiences, we work with a set of compositional principles to develop and evaluate our work from a visual standpoint. There are five main principles: balance, proportion, contrast, unity and sequence.
Balance
Does the design feel like it is in balance? Remember that balance does not equal symmetry—symmetry is only one type of balance. (And there is more than one form of symmetry: bilateral and parallel.) Asymmetry is both more difficult to bring into balance and more interesting visually—it is more dynamic than symmetry. Just as a seesaw can be made to balance by putting a small weight farther out and a larger weight closer in, larger and darker objects can balance with smaller or lighter ones.
Proportion
If you think of a tree, there is a clear variation in the proportion of the main trunk, the largest branches, the smaller branches, the twigs, and so on. The idea of proportion comes from nature and extends into the designed world. In classical Greek thought, the ideal form of proportion is called the Golden Mean or Golden Ratio—just a bit more than a one-third proportion.
Things that are different sizes in a design must vary in size enough so that they are clearly differentiated and are not ambiguous. Varying sizes help the viewer to determine the relative importance of different parts of the design and typography. This can extend to the whitespace margins on a page—smaller pages require less whitespace; larger ones require more. The margins between columns of type should be smaller than the margins around them.
Contrast
Simply put, contrast tells the viewer where to look first. But it is also aesthetically appealing because variation and difference are attractive to humans. Some types of contrast to keep in mind are the relative darkness (called value in color theory), weight, form, placement, quantity, texture, and scale. Without contrast, a designed piece may appear static, uninteresting, and hard for the reader to access because it is not immediately clear what to look at first.
Keep in mind, though, that different design traditions use more and less contrast. Historically, books in the European tradition were more about unity, proportion and sequence, therefore emphasizing the textual content. Advertising and other commercially focused designs such as posters emphasize contrast because it automatically brings interest and drama to their subject.
Sequence
In what order should the design’s elements be perceived? The use of proportion and contrast can help to establish the sequence. Why is this important? In a world where your readers have constant demands for their attention, the piece that helps them to easily understand it is the one that will get read.
Unity
Always in dynamic tension with contrast, unity can be overdone to the point where the design becomes rigid and lacks contrast. But unity in similar functions—for instance, all subheads are the same size and font—clarifies without stultifying. Another example of good unity is when a design coheres into a single unit instead of feeling like a bunch of disparate pieces. In general, the typography, color palette, and underlying grid of a designed piece all exert a unifying force that does not undermine contrast.
Finally
By combining the appropriate amounts of balance, proportion, contrast, sequence and unity, your designs can be eye-catching, pleasing, and easily understood—the goal of effective communication.
— Pat Thompson, creative director for web (but I haven’t forgotten what I learned in 20 years of print design work)
Parallel symmetry places equally sized objects on either side of an axis. Bilateral or mirror symmetry has the same shapes on either side of the axis in a mirrored arrrangement.
On a seesaw, balance can be achieved by opposing two same-size objects at an equal distance from the fulcrum, or two different-size objects at varying distances from the fulcrum. Symmetrical and asymmetrical designs can be brought into balance in the same way.
The Parthenon shows various golden rectangles which are claimed to have been used in its design. (Image used with permission from the Wikipedia’s discussion of the Golden Ratio.)
A flyer intended to let scholars at a university know about a call for papers was dry and had no focal point of interest. The redesign, while still very text oriented, lets the reader know at a glance what the topic is by using large and evocative typography.
A flyer invited students to be part of a leadership development program, but the design undermined the message by asking the reader’s eye to jump around the page from black box to black box. The redesign at right uses contrast at the top to tell the reader where to start, then uses the Western inclination to read left to right to describe the two parallel parts of the program, finally placing all of the contact and deadline information in a single, easy-to-find box at the bottom right of the page.