Am building a new iso at the moment, which will have some minor changes. First one is archinstall is included as another installation option. Archinstall has a few interesting features, not only can you do a basic normal arch install you can if you wish install a Window Manager and or other packages during process. Not going to go to much into that here but I will link archinstall project page, please visit and take the time to find out how it works.
Unlike Abinstall you do need a working network connection. Two options wired [should connect automatically] or wireless, the later is simply clicking on network icon in panel and selecting your network. If it is secure you will asked for its password to allow you to connect.
One thing I have done to allow pacman to work live is to uncomment mirrorlist. Given a network connection pacman should just then work live without the need to set up mirrors. However those mirrors may not be a local server related to your location and speed of connection might be slower. Edit of the uncommented file is a little more difficult as you have to remove all the open servers or pull in a new mirrorlist from archlinux generator. To help with this have backed up mirrorlist as mirrorlist.backup in /etc/pacman.d directory. So you have a copy to work from should your wish to use it.
May look at a connection testing script to make life easier, if connected then either pull in a mirrorlist or local servers or in this case switch in stock mirrorlist file.
After this you are as confused as I am 😉 You have to understand I look at this from a programmers perspective, how I can make this work.
Never been happy in shipping ArchBang with an uncommented list for this reason, it just gets too complicated and again relies on a network connection.
Please feel free to contact me if you do not understand any of this, again I thinking out loud after a long and very stressful week.