I have a new Asus G759JH laptop and it has Windows 8 installed on it. I have resized and fixed the partitions in a way I thought would work (now, I'm not sure that what I've done is actually going to work due to UEFI, which is the big problem here) but I have not dared touching the EFI partition other than mounting it to /boot/efi as a step on Arch's wiki suggested if you wanted to use the EFISTAB boot option. (?)

So, I got to the step where I would normally install grub and chain-boot it through windows->grub->arch but I didn't want to mess anything up because I don't have time to do recovery work on it if I do mess up...

Anyway, so to the point:

I have my partitions for Windows, like normal, and my partitions for Linux. The Linux partitions are on the SSD disk along with the partitions for Windows. And What I'm not sure is how to give me the option of booting either Windows 8 or Arch as soon as possible. With that I mean where/how do I set it up so that I can pick either one as early in the boot process as possible.

What I gathered about UEFI is that each OS can have their own EFI firmware or something and that you could boot different ones and go that way, or chain-load it if I go into Legacy mode. Or something like that. This is the whole reason I'm asking this question, becuase I'm very very confused.

So how do I add the option of booting Arch through UEFI and not Legacy mode? If possible.

Edit:
One thing that confused me that I would want clarified is this: If I have Windows on the EFI partition (which btw is only 100mb, but as far as I know I can't resize without wiping windows) does grub just add my ArchLinux entry to it or is it a chain-load or is it wiping it clean?

That's where I actually got stuck yesterday when I tried to do it on my own. I wasn't sure what it would do so I didn't do anything without being certain.