The .stl file generated by Craftplicator is a single-color file that can be used for 3D printing. A detailed description of this most commonly used file format for 3D printing can be found on Wikipedia. In order to 3D print STL files, you need to prepare it with a "Slicer" program configured for the 3D printer you want to use. The "Slices" translate the STL model into printing instructions (usually called GCODE) for your specific 3D printer. A detailed description of Slicers can be found on Wikipedia.