If you want to connect your facebook or gmail account to your OPIN account, just follow the steps below:
1. Click on  next to your username in the upper right corner and select account settings in the drop down menu.
 next to your username in the upper right corner and select account settings in the drop down menu.
2. Select the tab 
 account connections in the menu on the left hand side.
3. Click on the social network button (facebook, gmail) you want to connect your OPIN account to.