How to back up the contents of your Home folder to an External Hard Drive.
- Locate Go in your menu bar and click Home or press ⇧⌘H.
- Press ⌘A to select all the contents in your home folder or hold ⌘ and select the desired folders.
- Insert your External Storage Device, it will mount on your Desktop and Finder sidebar.
- Drag the highlighted content to your External Storage Device. A progress bar will appear, allow, time for this process to complete.
- Open your External Storage Device to verify your files match your home folder.
Detailed backup directions can be seen here, https://www.youtube.com/watch?v=ldjoD4zql8w