By their covers.

First class each semester I hand the students a questionnaire. One of the questions asks the students to draw, from memory, the cover of their favorite book of all time. I superimpose the drawings over a photo of a blank book, then show them to the students the following class.
Spine Out, “Favorite Book Sketches”

Related: The Times on books as decorations and the dying art of judging commuters by their reading preferences.

And then we could fuck it up a little.

The Tiger Mother roaring perilously close to meme-dom has finally encroached on Design Observer. The payoff is a bit of remembered wisdom dispensed by Tibor Kalman to Michael Bierut on the rules:

Tibor listened patiently to my ideas — there were lots of them — and then paused for a long time. “Well, yes, you could do some stuff like that,” he responded carefullly. “Or, we could do something like this. You could work out a good clear grid. We could edit all the images really carefully. Then you could do a really nice clean layout, perfect pace, perfect sequence. You know,” he added with a smile, “sort of like a Vignelli book. And then we could fuck it up a little.”
via Design Observer

This is a good read, especially for designers who fall into the trap of casting creativity and technical purity at opposite ends of a spectrum.