In order for your users to login via Facebook you need to register for a Facebook key.
- Go to https://developers.facebook.com and register for a developer account.
- Create a Facebook app via https://developers.facebook.com/apps. Instructions for creating a Facebook application can be found here: https://developers.facebook.com/docs/apps/register.
- On the “Product Setup” page, click the Dashboard link on the left-hand side.
- Save the App ID and App Secret values so you can add them to the MarketplaceKit Admin Panel