Not stupid questions.

The sequence is:

1 Create the object in a CAD program.
2. Save the CAD file in stl format. (Or download from Thingiverse, etc)
3. Generate the Gcode by running the stl file through a slicer program such as Slic3r, or whatever floats your boat.
4. Send the Gcode to the printer either via its on-board SD card reader, or via Pronterface on your PC.
5. Load your filament and press the GO button
6. Watched and be amazed!

The vast majority of stl files downloaded from Thingiverse have been printed by the designer, so the glitches have been removed and the stl files are ready to go.

OME