It's also possible to save the design to a Grid file, which is the file format used by Extrudifier, and then later load this file. If you don't want to mess around with files, the tool will generate a URL that can be visited again to retrieve the design.
The tool is hosted here: http://extrudifier.appspot.com.
This is how I use the tool to go from a 2D design to a 3D printed object...
Once the design is ready, I export it into a SCAD file and load it in OpenSCAD.
In OpenSCAD, I then Compile and Render (CGAL) from the Design menu and then Export as STL from the same menu once the object is compiled. This gives me an STL file to use.
Once I have the STL file, I load it up in Cura.
Cura will create a gcode file that I can then 3D print.