General :: Net Boot From Debian Server Using Directly Connected Ethernet Cable

I have a computer with grub installed, and nothing else. I'd like to install Debian on it without having to burn a CD. (and I don't have any flash disks.) It has a nice ethernet card, and I have another computer right next to it with an ethernet card. I also have an ethernet cable. However, I don't have any router free which I can mess with for these purposes. As I've looked up, apparently modern Ethernet cards don't need crossover cables, normal cables will work for this type of connection.

I've tried several different "tutorials" on how to set up a netboot server, but

None of them are complete. All of them assume that you understand how DHCP works, and that you can do things like set up a dnsmasq server. I don't understand the DHCP protocol, with submasks and whatnot (I know that it is the protocol for assigning computer network addresses, and that's it), and I don't think I should have to in order to simply connect two computers. All of the tutorials give you incomplete configuration files, and ask you to fill in things which I don't understand, and for me it doesn't make sense to customize these settings, as I just want to connect them and I really don't care what ip address the TFTP server has or whatnot. All of these assume that you are going through a router. I am not. When I try googling for ways to directly connect two linux computers with an ethernet cable, I can't even find instructions, just more references to "you need crossover cables".

So basically, I have two computers directly connected by ethernet cables. Tell me what packages I need to install, what the contents of my configuration files should look like, and what, if any, commands I need to run in order that when I turn on my second computer, and select network boot, it will start up a minimal debian system.

EDIT: Hmmm, it looks like I actually have a linux kernel installed too, but no root filesystem (so no other programs besides busybox).