I came to design from engineering via usability. Usability gives you metrics you can qualify your UIs with, just like you have for your code. Time on task is

I came to design from engineering via usability. Usability gives you metrics you can qualify your UIs with, just like you have for your code. Time on task is like execution speed for people. Information efficiency is like lint checking for content. I started with Jef Raskin's _The Humane Interface_. Chapters 1-4 cover the essentials about testing and usability and efficiency, and then Chapter 6 from 6.3 on, and you can skip the rest. Then, assuming you understand semantic HTML, you can take efficiency and semantic HTML and understand information architecture and 2D content layout. Robin Williams' _The Non-Designer's Design Book_ and Jan V. White's _Editing by Design_ can teach you effective and attractive positioning of content on a page or on a screen. The principles are all the same. From layout you can get into visual design through things like dashboards (Stephen Few's _Information Dashboard Design_) or other "practical" subjects without ever getting into becoming an actual artist. If you want to get more into visual design, I've given out a few copies of David Kadavy's _Design for Hackers_, and it's supposed to be good, but I haven't read it. The best way is really to take some introductory visual design and art classes. Check your local community college. If you want to get more into user experience or interaction design, Dan Saffer's _Designing for Interaction_ is often cited as a good overview of the practice of interaction design, but I haven't read it, either.