Login to your admin panel.
To view facebook connect extension settings go to System->Configuration->Excellence->Facebook Connect.
Just fill up these few fields and you are good to go.
First of all Set status Enable to activate this extension.
For Application Id and Secret Key follow these steps-
Log In to Continue
For Application ID- Click this link https://developers.facebook.com/apps, given as hint, after login below page will come up with Create a New App button in the upper right corner.
Enter the name you want to associate with this APP, Contact email is auto filled with your Facebook id, just choose category and click on create App Id button, complete security check.
After successful check, you get the page with your app name where you can find your App Id and Secret key credentials.
Now copy these credentials and come back to your admin panel facebook settings and paste your Id and Key, and click save config button.
Note Make sure to make your app live, so that any user able to login from there respective facebook id. To do so Go to your App->App Review and click on yes button to make testing public.
Now go to your web store and check out your extension.