To use webmail you will need to go to http://yourdomain.com/webmail (substitute "yourdomain.com" with your actual domain name).

Login with your personal username and password

To create new mail, click on the 'Compose' link. When finished, click 'Send'.

To view mail sent to you, you must click on the subject of the message you wish to view.

While viewing the message, you can easily reply to the message by clicking on the 'Reply' link.

You can delete messages easily by toggling the checkbox infront of the message you wish to delete, then clicking the 'Delete' button.