If you've added new contacts to your email account and want to bring them into Refer.com you can do a manual sync by following the directions below. Though, doing it manually is not required as the system will automatically sync every 3 hours.
To manually sync, select your name at the top-right of the screen followed by Settings.
Click Connected Accounts on the left.
Next to the connected account listed, select Sync.
The system will start to sync your contacts and could take up to 10 minutes to pull everything in.