Here below example for 10.4

Example for 10.3 and 10.5

Before starting, to avoid errors while setting up Mail, make sure that you are connected to the Internet. If you cannot be connected to the Internet, you may still set up Mail, but additional steps will be required.

1) In the Dock, click on the Mail icon. 

2) If this is the first time you've opened the Mail application, you will immediately be brought to the New Account setup assistant.

Click the Continue button at the bottom right and skip to step 6 below.

3) If you've opened Mail before, wait for Mail to open then click on the Mail menu at the top left of your screen and select Preferences. 

4) Click on the Accounts icon at the top of the window.

5) Click on the plus sign ( + ) at the bottom left of the window, circled in the example below. 

6) In the General Information area, set the Account Type to "POP."

a) Enter "Main Account" (or a description of your choosing) for the Account Description.
b) Enter your name in the Full Name field.
c) Enter your e-mail address in the Email Address field.

    The window should now look like the example below.

d) Click the Continue button.

7) In the Incoming Mail Server area

a) Enter "mail.yourdomain.com", substituting"yourdomain.com" with your actual domain name into the Incoming Mail Server field. ( ex: mail.wcpdemo.com) 

b) Enter your username into the User Name field

c) Enter your password in the Password field.

    The window should look like the example below.

d) Click the Continue button.

Click the Continue button and go on to step 8.

8) In the Outgoing Mail Server area, enter "smtp.yourdomain.com" in the Outgoing Mail Server field. (ex: smtp.wcpdemo.com)

Or enter your ISP's SMTP.

The window should look like the example below.

Note: Certain Internet Service Providers (ISPs) require that you use THEIR SMTP servers for Out going mail.

Check with your specific ISP for exact Outgoing server settings 

Click the Continue button.

9) The Account Summary area should look like the example below.

Click the Done button.

11) If this is the first time you've opened Mail, you will see the "Welcome" dialog box below. You will not see this "Welcome" dialog if you've opened Mail before. 
 Click the No button.

If the "Accounts" preferences window is still open, click the red close bubble button at the top left of the window to close it.

 12) Mail is now configured to send and receive e-mail.