There are many design principles that apply to artwork across the board. Whether you're interest is sketching, painting, photography, interior design, scrapbooking or some other artistic pursuit there are techniques to use that have been tried and proven. One of these "rules of thumb" is the rule of thirds. Have you ever wondered why one layout works while another seems kind of boring or uninteresting? It could be all about technique. I've got a post that goes into a little more detail that you might find interesting. You can find it here.