1. Go to the mail setup screen.

From the iPhone main screen, tap Settings > Mail > Add Account. This makes the new account screen appear.

2. Choose the "Other" account type.

Tap Other at the bottom of the new account screen:

This makes the "Enter your account information" screen appear.

3. Enter your account information.

Leave IMAP selected at the top of the screen, then type the following settings. (This picture is showing generic settings — use the box at the top of this page to enter your real e-mail address and show the actual settings for your account.)

Some things to bear in mind:

4. Go to the advanced settings screen.

Although the steps above are sufficient for basic e-mail, you need to do one more thing to make sure your iPhone properly stores sent messages, deleted messages and drafts on the mail server.

First, go to the advanced settings screen. Tap the address of the mailbox you just created:

You'll see a screen that looks similar to the one you just typed your settings into, but if you scroll down to the very bottom, you'll find a new Advanced item. Tap Advanced:

You'll see a section titled "Mailbox Behaviors". We want to change all three "behaviors", so first, tap Drafts Mailbox:

That makes the "Mailboxes" screen appear:

Tap Drafts from the "On the Server" section, as shown in blue above. This saves that setting and returns you to the "Mailbox Behaviors" screen.

Repeat the same steps for the "Sent Mailbox" (choosing Sent on the server) and the "Deleted Mailbox" (choosing Trash on the server). When you've finished, the "Mailbox Behaviors" should look like this: