There are several tools that that makes designing for Drupal much, much easier.

In particular, we recommend the Theme developer module and also Firebug.

Many of you may know about Firebug already. It's a browser tool that allows you to inspect any CSS, HTML or JavaScript elements.

Think of Theme developer as a Drupal-specific version of Firebug. Using Theme developer you can click on any element of your Drupal site and get a breakdown of how it was built.