I looked for paper ephemera, and found pure white papel picados, the prayer-flag-like cut paper ornaments. In other parts of Mexico, they're hard to find, with plastic everywhere and paper nowhere. Since this is a Oaxacan art form, I found them in the huge Abastos Market.
In the Zócalo of Oaxaca, there's something amazing to see daily. My first morning there, it was a beauty pageant of pre-schoolers, complete with a full band. They know how to do the beauty queen wave already.