In order to install and configure Drupal for Facebook, you need to do these things first.
You are going to need a Facebook account. If you don’t have one, go ahead and create one now.
Drupal for Facebook's fb_devel.module, while not strictly required, is extremely helpful. It is HIGHLY RECOMMENDED to use this module to set things up. fb_devel.module requires the devel module (separate download). So go ahead and enable that module before installing Drupal for Facebook.
PHP has many optional extensions. Your server may or may not have these installed already. You can view a list of extensions installed by typing "php -i" on the command line of your server.
Facebook's PHP SDK will fail without: