This design is from the Mustansiriya Madrasa in Bagdad, Iraq - built in AD1227. While I can find photos of the Madrasa I cannot find photos of this particular design. What is clear is that the design work is done as carving in terracotta; colour is not involved.
First, following directions:
Showing the infrastructure:
The red lines show the repeatable shape:
The repeatable hexagon isolated:
The experiment with colour begins:
How it works out repeated - and then I have an idea about the centre space, which is confirmed by a little more investigation - and the colour experiment continues:
Single hexagon, with colour:
Copied and placed as tiles.