I've recently attempted experimentation with Arch Linux, and have managed to get an install with basic utilities, a network manager, etc going. I plan to use the Openbox window manager, with (at least, for now) the XDM display manager. Here's what I ran in the terminal:
pacman -S xorg-xdm xorg openbox
systemctl enable xdm.service
reboot
I then reboot the system, and copied /etc/X11/xinit/xinitrc to ~/.xinitrc.
cp /etc/X11/xinit/xinitrc ~/.xinitrc
I added the line exec openbox-session to the end of ~/.xinitrc. I also ran chmod +x ~/.xinitrc, just to be sure. Lastly, I added openbox to ~/.xsession, and made it executable, as well.
I reboot the machine, and am taken to the XDM login prompt. I'm able to sign in successfully, however I'm simply returned directly to the login prompt. I'd like to go from login, directly to the Openbox "environment".
I admit that there is much here that I'm unfamiliar with. I've used Linux for some time, however I've done little "technical work" with windowing systems, window managers, X11, etc, so I've likely made some trivial mistake, somewhere.
EDIT:
My ~/.xsession-errors file contains the error /bin/sh line 1: /root/.xsession: Permission denied. However, using lx -l indicates .xsession is executable?
Not sure why but, simply making .xsession executable with cmod again seemed to fix the issue.