Below is a list of settings / buttons that you should avoid as a non-technical WordPress admin.
Found on the “Menu” page under “Appearance”, this button will permanently remove a menu. It will not placed in a recycle bin or put into a revision, it will simply be gone forever. In older versions of WordPress, this button did not even popup with a warning, it would instantly remove the menu when clicked. In newer versions of it does at least notify you that removing a menu is a permanent change.
This is by far the most common way that we have found clients will “break” something on their website. Depending on the size/complexity of the menu that was deleted, it can be a fairly time consuming task to re-create the menu properly once it has been deleted.
Found on the “Permalinks” page under the “Settings” menu. When your website is setup, typically your permalink structure will be set to something that uses the “%postname%”, which will make your links more readable (making your page links look something like “http://www.yourwebsite.com/
Updating WordPress / Plugins
It’s a good idea to keep your WordPress and Plugins up to date, but you need to make sure you are updating properly. Typically, minor updates will not cause any issues with your website (updating a plugin from 2.10 to 2.11). When doing a major version update (updating a plugin from version 2.10 to 3.0), there is a good chance that just pressing the “Update” button will not be the only step involved in completing the update. More than likely some code will need to be modified throughout your website to make sure everything works properly with the new version. For this reason, all major updates should really be handled by your webmaster.
Theme Editor & Plugin Editor
These editors are found on the “Editor” pages on the “Appearance” and “Plugins” menus. The PHP and CSS files that run your website and plugins can be found in these areas, and they should not be modified from inside the back end of WordPress. If you are a more technical admin and need to make a modification to any of these files, you should download the file to your computer (making a backup would also be a good idea), make the changes in your favorite code/text editor (such as Sublime Text), then upload the file back to the server.