Hit the settings icon on the home menu.

Scroll down to find the "Mail, Contact, and Calendar" settings button and tap it.

Next you see the accounts page. Here we see this user has already added an account. You may see other options here, such as "Fetch New Data". But don't worry about the settings on the lower half for now.

Tap on the "Add Account" option.

Here you can set up the type of account you want to add.

Tap on the Other option.

You might see this screen next, or you might see the next screen, depending on your version of the iPhone OS. Skip ahead as needed.

If you see this screen, tap "Add Email Account".

We want to set up a POP3 account, called POP on the iPhone. Make sure you select POP by tapping on it.

Fill out all the information on this settings page.

Name: This is the name that people will see when they receive an email from you. Type in your name here.

Address: Your full email address (you@yourdomain.com).

Description: This will be the description you see on the phone in the Accounts menu. Most people put their email address for this option so that they can quickly access their different accounts. Type your email address here (recommended).

Depending on your iOS version, you may have to tap SAVE or NEXT here. Once you do, the iPhone will "look up the account" and you will see the rest of the information needed below.

Host Name: Your domain mailserver, which will always be mail.yourdomain.com

User Name: Your full email address (you@yourdomain.com).

Password: The password you selected (or was assigned to you) when your email account was set up.

Tap SAVE or NEXT.

Outgoing Mail Server Settings

Host Name: Your domain mailserver (same as above), which will always be mail.yourdomain.com.

User Name: Your full email address (you@yourdomain.com).

Password: The password you selected (or was assigned to you) when your email account was set up.

Tap SAVE or NEXT.

You may see this screen, which is saying that the certificate on the server is not recognized as safe. Despite this draconian warning, it is perfectly safe to use our self-signed server certificate.

If you want to see the certificate, or download it to your phone, tap details and when prompted hit "Accept".

Otherwise, tap "Continue" (recommended).

If you see this message and do not want to connect using SSL, tap YES.

It is recommended that you check your mail over a secure connection, however, so you should tap NO here.

If you do tap NO, you might see a message telling you that this account may not be able to receive mail. Tap "Continue".

If all went well, and the account was created successfully, you should be back at the "Mail, Contacts, Calendars" screen. And you should see your newly created email account in the "Accounts" list.

Tap your new email account and let's set up some Advanced Options.

Scroll down and tap the "Advanced" option.

If you want your email to be available for both your phone AND your home or office PC, make sure the "Delete from server" option is set to "Never". This will allow you to download and read your email, but keep it on the server so that you can also get it on your office or home computer.

While your are on this screen:

Make sure "Authentication" is set to "Password".

Note that if SSL is turned ON, your server port should be 995.
If SSL is OFF, your server port should be 110.

Testing your set up

Tap the "Home" button and then tap the Mail icon on your home screen (or wherever you have it stored).

Mail automatically downloads your email to your phone. You should see your mail rolling in!

That's it. Repeat this tutorial for other email accounts you have.