You can't win with technical SEO anymore, but it can sure turn a good site bad or a great site to good. Making sure you know your most important keywords and using them consistently across a series of "technical SEO" parameters modeled better on MOZ.com
than we can do here will insure you don't suffer SEO penalties and search engine robot confusion.
Don't let SEO become a preoccupation, but graphic designers should be aware of their sites' top keywords. Top keywords balance between having enough demand to make them worth getting and not so much demand ranking will be impossible.
Your vision and content should drive SEO not the other way around. Don't write something FOR SEO, but do modify your content strategy to incorporate terms where you have rank and can build a beachhead of Google and Bing acceptance.