Login to your gmail account and from the settings button on the right corner, click on settings, then click on the Accounts and Import tab as shown below.

From the Send mail as tab, click on Add another email address you own as shown below.

SMTP and Port stays the same, but enter your username, email address, and password. Hit add account button.

On the next window, enter email address and hit next

leave as import emails from mu other POP3 account and hit next

enter the username which is the full email address and password

enter citadelministries.net for POP server

check to always use SSL

hit add account

On the next window (Your mail account has bee added), confirm yes to be able to send mail as your email address
Next window leave defaults

Use port 465

Finally, On the next window enter the verification code you got from Google mail and verify you have access to your email address

If you are only configuring your gmail account to send your other email account email, the configuration window is similar to the one above

Also, check the box the reads:Reply from the same address the message was sent to

In order to send and email as the newly added email address, compose a new email and select the new email account on the From box. In the background, Gmail will contact your risingdc.com mail server and ask to send it.