Finder guides.
What Finder shows and hides: hidden files, the Library folder, and how deleting in Finder really works.
Where Are iPhone Backups Stored on Mac? Find and Delete Them
iPhone and iPad backups live in a hidden MobileSync folder on your Mac. How to find each one, tell which device it belongs to, and delete old backups safely.
StorageCleanupFinder
How to Show Hidden Files on Mac, and Which Ones Use Space
Press Command-Shift-Period in Finder to show hidden files on a Mac. What they are, which are safe to delete, and which are quietly filling your disk.
FinderBeginnerStorage
How to delete files on a Mac without regretting it
How to delete files on a Mac safely: the shortcuts, what the Trash actually is, why Put Back sometimes fails, and which deletions genuinely cannot be undone.
CleanupBeginnerFinder