UPDATE: I’ve now posted an updated Drupal 6 Theming Cheat Sheet.
The Drupal Handbooks are an exhaustive resource for learning all things Drupal. Unfortunately, sometimes finding just the information you need can be difficult. The Theme Developer’s Guide alone includes 14 sections, most made up of additional sub-sections.
With that in mind, I put together a Drupal Theme Developer’s Cheat Sheet that includes some of the most handy reference information for themers. The cheat sheet is specific to PHPTemplate, the most common theme engine for Drupal. The two page cheat sheet includes information on available variables, file naming conventions, sample code, and more.
If you have any corrections or suggestions for improving the cheat sheet, please leave a comment.
Download the PDF: Drupal Theme Developer’s Cheat Sheet