1. Enter ‘Developer’ application:
http://www.facebook.com/developers/
2. Select your application (Create one if you do not have one)
3. Select ‘Edit Settings’
4. On the ‘Authentication’ tab, Check the ‘Facebook Pages’ box of the ‘Installable to?’ field.
5. On the ‘Canvas’ tab, fill in the ‘Canvas Page URL’ and ‘Canvas Callback URL’. Canvas Page URL will be the url of your application. Canvas Callback URL will be the content of your application.
6. On the ‘Profiles’ tab, Enter ‘Tab Name’ and ‘Tab URL’. Tab URL will be the content that show on your page tab.
7. Click “Save Changes.”