How do I setup a rescue email for my iOS device / Apple ID?

Apple has implemented a variety of security features over the years to protect user data, such as credit card information and so on. Some of those features include the Apple ID security questions and backup email. Adding a backup email, or "rescue email" as Apple calls it, allows you to reset your security questions, and recieve account security-related notifications. You can set up a rescue email on the Apple ID account page by following these steps:

1. Enter your Apple ID and password on Apple ID account page.
2. Click the "Add a Rescue Email..." option in the Security section.
3. Verify your account by answering the two security questions. If you have forgotten the answers to your security questions you will need to contact Apple Support for help.
4. Click "Add an Email Address" and enter your rescue email.
5. Apple will then send a verification email to that address.