Use bold sparingly. When much of the body text is set in bold, readers complain of eye fatigue. Underlining should never be used either in body text or in headlines. By spoiling the shape of the letter, it makes text difficult to read. Be careful how you use boxes There s some evidence that boxes do not provide emphasis.
Modern readers appear to ignore anything printed in a box.
Probably, this developed from our habit of ignoring advertising in newspapers and magazines. Boxes are useful for additional and supporting information. Shading has the same effect as a box, in discouraging readers from considering the contents as part of the body text. Shading also reduces legibility. Avoid reversed text David Ogilvy, the advertising guru, says that copy should never be set in reverse.