Creating a backup of your Raspberry Pi data is essential, and following the steps below will help ensure your backup is both safe and secure.

1. Connect the USB drive to your Raspberry Pi.
2. Open a terminal and find your devices using lsblk or sudo fdisk -l. Identify your SD card /dev/mmcblk0 and the USB drive /dev/sda.
3. Run the backup command: sudo dd bs=4M if=/dev/mmcblk0 of=/dev/sda status=progress
4. Replace /dev/mmcblk0 with your source SD card and /dev/sda with your destination USB drive.
5. bs=4M sets the block size for faster copying.
6. status=progress shows the progress of the operation.
7. Wait for the command to complete. The command prompt will return, and you can then safely remove the USB drive.