Auto Login from tty
If you want to login directly from the tty without a display manager, this is a working method for Arch Linux
systemctl edit getty@tty1
Add this to the top, read the comment about changes. Change simon to your username!
[Service] ExecStart= ExecStart=/usr/bin/agetty --autologin simon --noclear %I 38400 linux Type=simple
This will write to /firstname.lastname@example.org/override.conf
if [ "$(tty)" = "/dev/tty1" ] ; then startxfce4 fi
to the end of ~/.bash_profile
Reboot and you will be logged in and XFCE4 started for you.
The only issue so far is logout will drop you to tty1 and if you exit that, you will be logged in and XFCE4 started again.
I was looking into this for an encrypted machine where the password is entered to boot.