How to configure xorg config on OpenBSD

You want to run XWindow (Xorg) rather than command line on OpenBSD. Here are the trick.
It should be also applicable for every system running Xorg as the X server like Linux, FreeBSD, Opensolaris, etc.

Login as root and run command below:

# X -configure
[snip messages]
Xorg detected your mouse at device /dev/wsmouse. 
Please check your config if the mouse is still not operational, 
as by default Xorg tries to autodetect the protocol.
Your xorg.conf file is /root/xorg.conf.new. 
To test the server, run 'X -config /root/xorg.conf.new'

If there are no errors and you can see the default xwindow of OpenBSD, the Xorg is successfully configured.
You have to copy the /root/xorg.conf.new to /etc/X11/xorg.conf file so you can simply type ‘startx’ via command line to start X window.