From the Mail menu, choose Preferences.

Ensure that 'Accounts' is selected from the buttons at the top, and then click on Create Account.

When the dialog box opens, select POP Account from the list of Account Types.

Now enter in your account information as shown above. Start by entering in a description for this account, followed by the E-mail address given to you by PortalMedia, and then enter in your name as you'd want it to appear on e-mail you send out.

Next, enter in mail.portalmedia.com for the 'Host name', then enter in your Account ID given to you under 'User name', and then your given Password.

Finally, enter mail.portalmedia.com under 'SMTP Host'. Check 'User authentication when sending mail', and then re-enter your given Account ID and Password under SMTP User and SMTP Password. Click on OK to close the window.

This will bring you back to the main window, where you will now see the account you've just created. Click on the red button in the upper-left corner of the window to close the window.