I do not teach those classes but a fellow instructor does. She uses a few large presentation size pieces of cardboard with the number and name of the station and only a number on the station itself. I am not sure whether this is easier than the way you are doing it but is seems to work for her, and her classes are very popular.
This is good just recently worked this out myself
What I’m finding works well for both large and small groups is a dry erase board. Label the stations by number and give them exercises. At each station have a number that corresponds with the number on the dry erase board. At the end of each round just say ok go to next station in which they shift in order to the next station. They just follow the group in front of them.
Just be sure to go over station assignments at the beginning near the warmup so once you get them going you don’t have to slow down the dynamics to explain anything.