You have surely seen Facebook with the Like button and the classic box with smileys on a fan page. Now we are going to insert them in our theme in the left sidebar by performing the following steps:
First, you need to go to https://developers.facebook.com/docs/plugins/like-box-for-pages/.
Then, set all the parameters to customize your Like box. Set Width, Height, and the other options. In the Facebook Page URL option, you can add your Facebook page link. The following screenshot shows the plugin configuration page:
After you have inserted all the fields, click on the blue button to get the code. In the pop up that appears, as shown in the following screenshot, select HTML5:
To enable the Lightbox script, you need an API key. You can get this at http://www.facebook.com/developers/apps.php, and create a new Facebook application.
Once you create your app, select the application from the drop-down list, and your code is ready to use.