Learning the Basics of Drupal Theming
The importance of themes in Drupal
The range and flexibility of Drupal themes
Working with the Default Configuration and Display Options
Controlling module and block visibility
Installing an additional theme
Understanding PHPTemplate Themes
Using Intercepts and Overrides
Overriding templates and themable functions
Working with template variables
Creating a new theme through sub-theming
Building a new theme without sub-theming
Designating a separate Admin theme
Dynamically theming page elements
Overcoming Common Challenges in Drupal Theming
Maintaining cross-browser compatibility
Creating template suggestions for fields
Creating template suggestions for specific nodes