To encrypt an email message, simply create the message and below the body of your message, include the words "Secure Message". Make sure to capitalize the first letters in Secure and Message, and then you can send it. This will only need to be done when sending an outside email (outside of JDK).
To view an encrypted message, simply download and save the message and then open it up with a web browser. Right click on your downloaded message and choose "open with" and then select a web browser of your choice.