Why not just try the attached noobs installer which I've added Arch Linux OS to? I added the Arch Linux files myself to noobs installer with files I found on Raspberry official forums. It works a treat and downloads direct from Arch Linux the latest version, partitions and sorts out you SD card etc. Way way easier than doing the official instructions on Arch Linux site. I don't have a linux computer so this was a much easier way to do things. Simply extract the contents to a fat formatted card... pop it in your Pi... choose whether you want Pi2 or Pi (for Pi3 like me select pi2) and away you go.
https://mega.nz/#!qhs1Ab5S!jPzzp9YWcdBl ... x1OAYC0UmcEnjoy. Hope it saves you some hassle. You'll still need to setup Arch Linux once it's installed but you'll have a virgin version of Arch Linux installed that you can quickly get going with. You don't need to rely on someone elses setup like the post before me. My Pi3 is all setup beautifully with Arch Linux Arm thanks to this little extra Noobs OS trick.
