Steps to Manually Update Sites

Take a screenshot of the homepage.
Create a backup point through WP-Engine.
Update WP-Core
Update theme
Update plugins
Compare the homepage to the screenshot, make sure the header and footer have not lost customization, or if there are any errors.
If something goes wrong then restore the backup (Point #2)
If any errors were present, document with specific details and screenshots, then email to Sharon and Peri.