Go to Gmail Settings

Click See all settings
Click Accounts
Look for Send mail as:
Click Add another email address
Enter Name and WebMail Address (name@yourwebsite.com)
Leave “Treat as an alias” checked
Click Next Step

SMTP Server: (ask our support about this) e.g. cloud33.hostgator.com
Username: (name@yourwebsite.com)
Password: Enter the WebMail account password
Port: 465

Click Add Account

Now go back to you Gmail Inbox and click the confirmation link