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. Break up long documents using subheadings 78 percent of those surveyed in one study said that they found subheadings useful, especially in long documents. Dennis G. Martin, Brigham G. Young University Mixing typefaces can make the job look like a dog s breakfast.
Most typographers stick to two typefaces in a book or report.
Many choose to use only one, but to use it in different sizes and weights. The size of the letter depends on the age and reading level of the audience, and the length of the line. Most people find it easy to read type within the range 10 point on an 11 point base to 12 point on a 14 point base. The base measurement is the distance between the base of a letter and the base of one in the line immediately below. Line length should be no less than 40 characters and no more than 60.