First, you open up some 3D modeling software (Tinkercad in this case) Then once you're done modeling you download the file as an STL, then move it over to the slicer, change the settings needed, download it as a GCODE file onto a microSD card, then you take that SD card to the printer and begin printing.
UPDATE: I am doing an experiment print on it. If you're wondering, my Tinkercad is https://www.tinkercad.com/users/bX9PRFnZy2k-ckrp2010 (when it is READY)
