This presentation was given at San Diego Drupal Camp, San Francisco Drupal Users Group, and Stanford Drupal Camp.
The goal was to give users as a step-by-step instruction manual for building a theme in Drupal 8. While not a requirement, some familiarity with previous Drupal versions (and Drupallisms like 'node' and 'hook') will be helpful. The first half is the nuts and bolts details of name conventions and folder structures. The second half is all about the amazing things that can be done with Drupal's new theme engine, Twig. Anyone who has grumbled about adding that one extra div (or removing it) will be pleased at the unprecendented control that Drupal themers and front-end developers from any platform now enjoy. The included code samples can also be used as a bare-bones starter theme.
Slides here: http://git.io/z-slides
See the latest code here: http://git.io/zakiya
Let us know what you think in the comments below!