serial console for dummies?

[Scott I. Remick]

Hello... I'm trying to set up a serial console for watching console error
messages while in X, but am having a real hard time getting my head around
the concepts of what I need to do (and don't need to).

I've seen http://www.freebsd.org/doc/handbook/serialconsole-setup.html but
I'm not clear about how much of that applies to what I want to do, since
it talks about setting it up for a headless system (no keyboard or
monitor) and actually instructs you to remove the keyboard. I've also
searched the mailing list archives but I've read a lot of conflicting
info, much of which for different uses of the serial console than what I
want to use it for, and I've now read back so far that I can't even be
certain that the suggestions apply to FreeBSD 6.0. Ugh

So is there someone who can give me a hand-held walk-through of just what
I need to do to make this work? I'm running FreeBSD 6.0-RELEASE and live
in X (Gnome) all the time. My intention here is to be able to see console
messages (Errors) so when something dies (like X locking, which happens
sometimes) I have a chance to see what the heck happened. I have an old
486 laptop I intend to use as the "dumb terminal", as well as the
necessary null modem cable. I just need to know what to configure on my
FreeBSD box so that console errors are mirrored to the serial port. Thanks!