This has come up before, but I still don't know the basic
procedure. I've installed debootstrap on a new disk and run:

  # debootstrap --arch amd64 jessie /mnt/debinst   \
      https://packages.devuan.org/devuan

I: Retrieving Release
I: Retrieving Release.gpg
I: Checking Release signature
E: Release signed by unknown key (key id 94532124541922FB)

No change when I downloaded and ran

# dpkg -i devuan-keyring_2015.05.05_all.deb

Do I have the right keyring? Was the alpha4 release date
c. 2015.05.05?

In simple step by step terms, what do I do?