I picked up a book recently called Design Elements: A Graphic Style Manual by Timothy Samara* that is quite good. Samara starts off his book — after a short discussion on what is meant by design and graphic design — with a list of "Twenty Rules for Making Good Design" which includes a brief but good elaboration of each of the rules. Now, as Samara points out, rules are important to understand but it's certainly permissible to break the rules (he even shows how later in the book). What is not permissible is to remain ignorant of the rules. Samara quotes Typographer David Jury here: "Rules can be broken — but never ignored." I tend to think in terms of Principles rather than Rules, though this is really just a matter of semantics. This stuff is old hat for longtime designers, but for the rest of us Samara's list of 20 Rules is a useful reminder. Here are just Ten of Samara's twenty rules below just as he wrote them (though not in this order). I chose the rules (principles) which I think are both the most important and yet easiest to grasp without much or any explanation. Keep these rules in mind when designing your next presentation or website, poster, etc.

10 design rules to keep in mind
   (1) Communicate — don't decorate.
   (2) Speak with one visual voice.
   (3) Use two typeface families maximum. OK, maybe three.
   (4) Pick colors on purpose.
   (5) If you can do it with less, then do it.
   (6) Negative space is magical — create it, don't just fill it up!
   (7) Treat the type as image, as though it's just as important.
   (8) Be universal; remember that it's not about you.
   (9) Be decisive. Do it on purpose — or don't do it at all.
   (10) Symmetry is the ultimate evil.

This list of ten above which I pulled from Samara's list of twenty are self-explanatory for the most part; let me clarify just two of them. Number 3 (Type). Remember that even within one family there is lots of variation possible (e.g., regular, light, ultra light, narrow, italic, bold, extra bold, and so on depending on the typeface), so consider even working with just one professional typeface family for a project and see what you can do. I have a preference for san serif typefaces but a combination can work well too in display type (such as Apple using Helvetica and Apple Garamond together). Number 10 (Symmetry). OK, symmetry isn't evil, in fact it can be quite beautiful, and calming, (or serious, etc.). But symmetry can also be rather dull and predictable. Asymmetrical designs are more dynamic generally and can allow for a bit more freedom of expression. Like the author, I have a thing for asymmetry myself (maybe because my nose is crooked from playing American football). The Zen aesthetic is all about asymmetry as well (Fukinsei 不均斉). 

Another good book
Another book I received recently that I really like is Graphic Design: The New Basics by Ellen Lupton and Jennifer Cole Phillips (a pic of my copy on posterous). This is a good book. It covers the fundamentals of graphic design, much of which has not changed over time (that's why they are fundamentals). But the author stresses some fundamentals such as layering and transparency that have become perhaps more important today for many reasons, including the fact that powerful digital design tools are ubiquitous and layering and transparency effects are easier to do now.

* I do not have Timothy Samara's newest book — Design Evolution: A Handbook of Basic Design Principles Applied in Contemporary Design — but it looks good. I'll let you know.