Windows: Right-click the folder
Windows: Select Properties
Windows: Check Hidden
Windows: Click Apply
Windows: Choose whether to apply to the folder only or subfolders and files
Windows: Click OK
Windows: Open File Explorer
Windows: Go to View
Windows: Turn off Hidden items to keep it hidden
macOS: Open Terminal
macOS: Use `chflags hidden /path/to/folder`
macOS: Press Return
macOS: To show it again, use `chflags nohidden /path/to/folder`
Linux: Open Terminal
Linux: Rename the folder to start with a dot
Linux: Example: `mv folder .folder`
Linux: Hidden folders stay hidden in most file managers
Android: Use a file manager with hide options
Android: Select the folder
Android: Choose Hide or make a `.nomedia` file if hiding media from galleries
iPhone/iPad: Move the folder into the Files app
iPhone/iPad: Store it in a less visible location
iPhone/iPad: Use app-specific hidden or locked folders if available