The WYSIWYG module is my favorite for rich text editing in Drupal 6 and Drupal 7. (In Drupal 8, WYSIWYG is in core.) Here's how I set it up.

Drupal form theming

After creating a custom form with FAPI (Drupal's Form API), it can be hard to theme it just like you want. Here's how to do some basic form theming including the creation of a template (.tpl.php) for the form. Note that the theme hook name must be the same as the form name.

Display Suite

Provides some advanced layout and display options for content. "Display Suite is a module that takes over the rendering of entities."