This is basically a rehash of an original post on CNXSoft - all credit (particularly for the Virtio device arguments used below) belongs to the author of that piece.
Download the latest uefi1.img
image. E.g. ubuntu-16.04-server-cloudimg-arm64-uefi1.img
from https://cloud-images.ubuntu.com/releases/16.04/release/
Download the UEFI firmware image QEMU_EFI.fd
from https://releases.linaro.org/components/kernel/uefi-linaro/latest/release/qemu64/
Determine your current username and get your current ssh public key: