Setup the Facebook Application - Part 1, on Facebook.com

The following steps assume you have a Facebook account.
• Go to http://www.facebook.com/developers/createapp.php.
• If asked to login, use your Facebook login. If you haven’t created an application before, you will be asked to grant Facebook Application access to your Facebook account. You have to allow this in order for this process to work.
• Facebook will ask you for the Application Name that you want to use. This is a short human-readable name. It will be viewable to those who are allowed to visit your Facebook account so make it simple and clear.
• Agree to the terms and click Save Changes. Note: The next page that appears will contain three pieces of information that you will need for your Drupal FB Application: API Key, Application Secret, and Application ID. You will copy and paste this information into the applicable fields when creating your Drupal FB Application.

Canvas Page-specific Setup

Not necessary for Facebook Connect-only applications.
• Click on canvas in the left menu of your Facebook application screen. At the top of the screen that appears next, fill in the URL field. Keep the URL simple and descriptive. Formatting restrictions are provided on the screen. Please read them.

Setup the Application - Part 2, on Drupal

In your Drupal site, as an administrator, go to Admin >> Site Building >> Facebook Applications >> Add Application. Configure the following:

• Title – Brief title for you application (human-readable)
• Label – This is your machine-readable name. Use lower case, no spaces. If you have more than one Facebook application in one site, this will have to be unique for each. If you are running both development and live servers, you should use the same label from one server to the next.
• API Key, Secret, and Facebook App ID – Copy and paste this information from your Facebook application screen.
• Set Application Properties Automatically – Make sure this is checked.
• Facebook user settings – Leave default settings here, unless you're an advanced user.
• Facebook canvas page settings (for Canvas Page apps only) – Set the theme to be the fb_fbml theme that you enabled earlier. If you do not see it in the drop down list, it was not enabled.
• Facebook Connect settings (for Connect apps only) – Check the box to make this the primary application.
• Save your configuration.

Congratulations. You have a Facebook Application, now powered by Drupal!