Steps

Screenshots are from GNOME but most GUI desktops are similar.

  1. Select install tarball wherever you have it downloads (often in your Downloads directory), right-click and select ‘Extract To…’ File manager showing extraction of install tarballFile manager showing extraction of install tarball

  2. Browse to the boot partition of the SD card Initial directory when choosing directory in which to extract install tarballInitial directory when choosing directory in which to extract install tarball

  3. Select the boot partition of the SD card as extraction destination We have selected the boot partition as the destination for extracting the install tarballWe have selected the boot partition as the destination for extracting the install tarball

  4. The result will be a directory containing the boot files on the boot partition; we actually want the files in the top-level (root) of the boot partition. File manager showing directory creating boot files created in the boot partitionFile manager showing directory creating boot files created in the boot partition

  5. Therefore, select all files in the directory that was created (e.g. in the file manager, browse into the directory and press [Ctrl-A]). File manager showing all files boot files in directory from tarball selectedFile manager showing all files boot files in directory from tarball selected

  6. Cut and paste the files into the top-level (root). File manager showing the boot files moved into the top level of the boot partitionFile manager showing the boot files moved into the top level of the boot partition

  7. Remove the now extraneous extraction directory (which should be empty). File manager showing result of removing the now extraneous extraction directoryFile manager showing result of removing the now extraneous extraction directory