I'm surprised they didn't have ready made posters
They finally realized that no one is impressed by that. Plus, the ones running things are also suffering capital drain in this political economy.
So, it looks as though many of them grabbed cardboard and markers and made signs. Probably called the Signs Working Group. Those signs are arranged on the ground at the occupied site. Protestors simply walk by and pick one up. When they are done, they put it back. Repeat the next time. Is it a coincidence that _all_ the signs are written on scrap cardboard?
However, they did put thousands into a 4-color broad sheet free newspaper.