What is the official DC Comics Superman reading order ?

What is it you want to read specifically, do you have an era you're intrested in? There's 1000s of comics and they don't all take place in an order. Here's a link of every superman comic in the main universe from 1986 to 2011. After this the universe rebooted and all of this became non canon. But then a few years later they changed their minds and said some of it was canon. Comics are sometimes pretty confusing. http://www.comicsbackissues.com/comic-book-reading...

As Superman has been continually published for 82 years now, there isn't one.

Further, the limited series Doomsday Clock has modified the Superman history, as well.