For example, its guidelines on typefaces:
Use the most legible face available to you. Experiment with several, then choose the one you find easiest to read. Type with a larger “x-height” (that is, in which the letter x is taller in relation to a capital letter) tends to be more legible. For this reason faces in the Bookman and Century families are preferable to faces in the Garamond and Times families. You also should shun type designed for display. Bodoni and other faces with exaggerated stroke widths are effective in headlines but hard to read in long passages.Our new favorite font, Georgia, is good on x-height.
I don't follow every rule or tip offered, but everything the court suggests is worth thinking about. If you've never looked at it before, you really should.