The last thing I wanted was a shower curtain rail at head height in the tiny space. There are commercial solutions out there which are similar to this, but I could not afford them. So I had to invent a low-cost way of keeping the shower curtain and rail out of the way when the shower was not being used.
Step 1: The curtain track
My two shower curtains are required to cover only two sides of the square, as the ensuite walls in the shower corner are the other two sides. The third side of the track is used to let the curtain return into the corner when not in use. (In the picture, you can see the curtain suspension cords in the corner descending from the curtain track on the ceiling.)
There are enough gliders on the track for one per hole of the two curtains (allowing for a two hole curtain overlap), with "assistant" gliders between each of these, and a few gliders for the side which does not have a curtain suspended from it.
The picture shows the ceiling with the shower head pushed out of the way against the wall.