[runnerup]

I recommend this, it's exactly how I handle it in Ubuntu at least. I also often use Arandr in addition to xrandr, there's one feature (positioning the tiles if you have a very nonstandard setup) which is way easier to use in Arandr. But Arandr also lacks a lot of options that xrandr has.

You can do it all with xrandr IIRC, but not with Arandr. Arandr just helps with positioning if you have say, three monitors of different sizes which don't line up in any typical way.