I am trying to install Arch on a USB flash drive. However I have few questions... in particular about pratitioning and UEFI.
What partition table should I use? dos or gpt? and from this... what partitioning tool should I use? (cfdisk, parted, gdisk... etc)?
Also... I am going to be using this USB flash drive with a new computer that has a UEFI BIOS. Should I do anything different because of this? (Have a different boot flag?)
I think you need to read up on UEFI. Depending on what partitioner you use the boot flag can mean something entirely different.
MBR(dos) or GPT is a personal preference, so asking that is like asking someone else what your favorite soap should be. There is one exception though. I have heard of some systems that have firmware bugs that won't allow GPT/bios and some that won't allow MBR/UEFI. There are also some machines that won't do a damn thing if they aren't MBR partitioned, but those all tend to not be UEFI.
As far as the tool to use, if you want to use GPT then use gdisk and friends, of you want to use MBR(dos) use fdisk and friends. Or you can learn how to use parted, which can apparently handle both. But, for example gdisk offers a number of different tools that can all achieve the same thing. Again, it is like asking someone else if you should prefer boxers or briefs...
I choose boxers, they don't cut the meat.....
-I can give you a ladder, but you need to climb it yourself-
I get used to boxers one a while brief is ok lol