[Accessing Mail] Mail is the program that looks like a stamp on your screen's dock, click the icon to start the program.

When you've started mail, click [Mail] in the menu bar and select the [Preferences...] button.

[Account Setup] You should be presented with a screen similar to the one shown below.

Fill in each field as shown in the image, substituting your domain and user names where necessary. Hit the [OK] button.

*Note: It is important to note that because there are multiple versions of Mac OS X, your Mac Mail setup menu may not look like the one pictured. All fields should be similar though, and can be filled in with the proper corresponding information.

[Import Mailboxes] The next box to pop up will ask you whether or not you'd like to import mailboxes from another client. Click the [No] button, and your Mac Mail should be ready to use with your email account.