Adding a secondary email address is one way to protect yourself in case you ever lose access to the primary email address on your account. You can add or edit your email addresses from your Account Settings page:
Click the Email section.
Click Add another email and enter your new email address
Enter your password and save your changes
Check your email for a message from Facebook with instructions on how to confirm your new email address and complete this process
We also recommend reviewing the overall security of your account and updating your security information.