Check the public version
Open the actual domain on desktop and mobile. Check the primary navigation, key landing pages, images, downloads and language links. Test a nonexistent URL so you know the site returns a useful error page instead of a misleading success.
Verify the destination
A form animation is not evidence that an inquiry arrived. Use an authorized test and check the receiving inbox or system. For email links, check the address and prepared message; opening an email application is not the same as sending the email.
Make operations repeatable
Document how to edit a page, publish a change and restore a previous version. Record who owns each external account. Keep a launch checklist with evidence so future changes can be checked against the same practical standard.