I am also getting a chip installed in my 1.6 / 1.6b Xbox this Friday.
Your best bet is to simply read all the tutorials, and read some more. The information maybe outdated since 2004, but remember the fact that the Manufacturing dates for the consoles ended around that time, so there have been no newer original Xbox models coming out.
So you need to consider the information written is up-to-date as it's gonna be in terms that the Xbox IS a last generation console several years old.
Here is some useful information for what I recommend, since I was once in the same boat as you, not knowing from chip to flash to softmod to hardmod, It was all alien until I read up on those tutorials and gave myself a education to understand what exactly I am going to be doing to my console and know exactly what I am getting in the end.
XBMC is also what was the final convincing for me to really push and get my console modded.
Here is are my first recommendations as a prep-to-do before you mod your console.
1) BACK UP THE EEPROM!! AND C: Directory
The eeprom is the a key that registers the Xbox stock drive to the motherboard in a form of "marriage" Meaning the stock drive that comes with the Xbox is married to stock motherboard it comes with due to the bios assigning itself to it. The eeprom.bin is very useful for that when you install a larger hard drive it will be a simpler process...I cannot stress enough how important this is. As I have read many a topic where someone screwed up something on thier Xbox and needing to revert to stock settings and not having the Eeprom make the process much much more difficult.
Backing up your C: Directory ensures that you have a backup of the original M$ Dashboard.
If something goes wrong and you need to revert to the original Dashboard to fix something such as setting the system clock due one of the many number errors. Or needing to set the screen format to NTSC or PAL if your system accidentally changes it's native setting and you can't undo it for some reason.
2) get one of the PC FATX naming utilities here = http://www.xbox-scene.com/tools/tools.php?page=managers
These will allow you to get your files in the proper naming format. So when you copy any files to your Xbox after you mod it, they won't be rejected by your copying program.
3) get a Xbox File manager. Such as XCommander, BoXplorer, And / Or DVD2Xbox.
If you install XBMC OR another program in the wrong directory, well that is what these tools are useful for.
Also DVD2Xbox allows you to copy your original Xbox games to your HDD to be played directly from the system itself, allowing you to preserve your original DVDs to prevent scratching and wear from extended use.
If anything else comes to mind, I will be sure to add it.