You have to print every pixel in the "desired" color. For easier printing they are named accordingly to a color. In addition you can see the "type" of block in the name as well as the number of blocks you have to print from this type and in this color.
E.g.: “Light grey x4_38”
This transfers to:
Use the image as a reference for building your pixelart. It took me around 0,5h to assemble and only ~ 40 hours to print. I recommend laying out all Pixels first and assembling it after you arranged all pixels. :)
I recommend printing a bunch more snap fits. Because you will have to break them if you made an error during assembly. ;)
I also made one which you can see here: