It's the same idea of Nerdforge's Hexaleaf project: https://www.youtube.com/watch?v=2OP-oEbzB6g

Short video of the making process: https://youtu.be/NzVO-1mSUtA

This version uses less plastic and have a reflector at the bottom for light efficiency. If you print this correctly, you are unable to see the supports through the walls of each hexagon because the wall only have 2 perimeters without infill( for a 0.4 nozzle).

For better light efficiency of the bottom reflector and hexagon walls, I use a aluminum foil tape and use a credit card or plastic to flatten it(see the photos).

Each hexagon is 19cm side to side (is bigger than other versions) so I use 38 adressable LEDs for each one.

WARNING(thanks to TVercruysse):be aware that aluminum foil is conductor, so make sure that your led strip don't make a short circuit with the aluminum foil of the wall where you glue the strip.