First thing you need to do is to convert Sketch Up to .stl files. You can find and download this here su2stl.rb, which can download from this page. The next thing that you need to do is get the .stl files into the Sketch Up Pluggins. To do that you need to copy the .stl file into the pluggins file here C:\Program Files\Google\Google SketchUp 6\Plugins. Then make a 3D image on SketchUp, the design should only be 1", 1", 1" when you first start to make it easier.