I've tried to draw the plan with dia, gimp and inkscape, but that was too dificult for me. Is there better drawing tool for that?
- Drawing in PythonCAD was straightforward, but it had trouble printing or exporting to a printable format.
- SagCAD's interface came across as bizarre and unintuitive. It looks like it's more oriented toward 3D sketching.
- QCad Community Edition worked well. I suggest giving it a try.
All of these are available in the Ubuntu Software Center.
A ruler and a pen? Inkscape is the easiest IMO