Once you’ve downloaded an image, write it to a USB drive (or a microSD card) and boot from it. The general steps are the same for USB and SD media, just make sure you target the right device.

Linux

Find your drive first:

lsblk

Replace /dev/sdX with your actual device:

sudo dd if=vitruvian.img of=/dev/sdX bs=4M status=progress oflag=sync

Then reboot and select the drive from the firmware boot menu, usually F12, F11, or Escape at startup.

macOS

Find your disk, unmount it, then write:

diskutil list            # note your disk, e.g. /dev/disk2
diskutil unmountDisk /dev/disk2
sudo dd if=vitruvian.img of=/dev/rdisk2 bs=4m

The r in /dev/rdisk2 matters: the raw device writes much faster.

Windows

Use Rufus in DD image mode. In the partition scheme dropdown pick the GPT/UEFI option if your machine boots that way.

MicroSD cards (boards)

Exactly the same as USB, just against the card’s device. For arm64 boards use the arm64 image. See the boards site for board-specific notes.

What happens next

Boot from the drive and you land on the first-boot screen; on live media that’s the language picker and Try/Install option. The details are on the First Boot page.