How to write in Cuneiform

"Cuneiform" is a medium, sort of like "paper" if that included the tool you use to make the marks.

Writing systems using cuneiform include Sumerian, Akkadian, Hittite, Hurrian, Ugaritic, Old Persian...

The article states that "Prop­er­ly writ­ten out, these syl­la­bles join up into a flow­ing cal­lig­ra­phy that your aver­age, edu­cat­ed Baby­lon­ian would be able to read at a glance", so presumably they're thinking of Akkadian. Why not say so?

(Does it make a difference? Consider that our first attempt to read the name of Gilgamesh came out as "Izdubar".)

The Babylonians also used Sumerian as a prestige language long after it was dead, much like we might use Latin today. Also, reading Akkadian cuneiform involves learning a bit of Sumerian vocabulary, because texts spell out words in Sumerian that were presumably pronounced instead as the appropriate Akkadian word (Sumerograms).