How to configure the FCKEditor using the WYSISYG module

The basic installation is very straightforward.

Download and install the module like any other Drupal module.
Go to Administer » Site configuration » Wysiwyg, and follow the installation instructions that are displayed there

Make sure you set the toolbar location to be on top otherwise you'll ennd up with a missing toolbar

See documents below for configuration and here for troubleshooting.