See the black plastic cap at the end of the wiper arm? To avoid unsightly marring, carefully pry it off. You'll need to do this on both the driver's side and the passenger's side wipers.
I used a small slotted screwdriver to pry the cap loose.
When the cap is removed, a small nut is visible.
Remove the nut from the wiper spindle assembly with a 13mm socket and racket handle.
13mm!
Before I removed the wiper arm, I used blue painter's tape to mark the location of the wiper blades for future reference.