1. Ensure the USB stick is formatted using FAT32.
2. Download the BIOS update from http://www.dell.com/support/home/uk/en/ukbsdt1/product-support/product/xps-13-9360-laptop/drivers.
3. Copy BIOS update to the USB.
NOTE: The BIOS will end in an .EXE extension. Even though Linux can’t open it natively, it will be processed by the BIOS properly.
4. Reboot the system, and press F12 at the Dell splash screen.
This will bring up the One time boot menu.
5. Select the option to BIOS Flash Update.
In the popup, navigate to your USB disk and select the BIOS you downloaded.
Once the update has been completed, the system will reboot automatically.