When designing pictorial representations of objects, whether they are icons or graphical buttons, begin by defining the icon's purpose and its use. Brainstorm about possible ideas, considering real-world metaphors. It is often difficult to design icons that define operations or processes — activities that rely on verbs. Consider nouns instead. For example, scissors can represent the action of Cut.
Draw your ideas using an icon-editing utility or pixel (bitmapped) drawing package. Drawing them directly on the screen provides immediate feedback about their appearance. It is a good idea to begin the design in black and white. Consider color as an enhancing property. Also, test your images on different backgrounds. They may not always be seen against white or gray backgrounds.
Consistency is also important in the design of graphic images. As with other interface elements, design images assuming a light source from the upper left. In addition, make certain the scale (size) and orientation of your graphics are consistent with the other objects to which they are related and fit well within the working environment.
Avoid using a triangular arrow graphic similar to the one used in cascading menus, drop-down controls, and scroll arrows. When this image appears on a button, it implies that the control will display additional information. For example, you can use an arrow graphic to designate a menu button.
You may want to use a technique called anti-aliasing when designing graphic images. Anti-aliasing involves adding colored pixels to smooth the jagged edges of a graphic. However, avoid using anti-aliasing on the outside edge of an icon because the contrasting pixels may look jagged or fuzzy on varying backgrounds.
Finally, remember to consider the potential cultural impact of your graphics. What may have a certain meaning in one country or culture may have unforeseen meanings in another. It is best to avoid letters or words, if possible, as this may make the graphics difficult to apply for other cultures.
Note
For more information about designing for international audiences, see Chapter 14, "Special Design Considerations."