If you wish to make any garland out of WS2812 led strip, you will probably need:
1. some shade for LED
s to produce more consistent light;s flat surface.
2. some protection for sensitive strip connectors.
With the files included you could print as many shades as you need for your project.
Just print two parts and slide them together via dovetail connection.
Use white PLA, 0.2 mm layer height, any infill, no supports.
Rotate in your slicer part called Led1 to face the buildplate with it