Draw all (or most) lines with the Bezier tool ("Draw Bezier curves or straight lines"). The keyboard shortcut to select the Bezier tool is pressing "B".
Things to not do
Do not send me .dwg files
Do not send me .dxf files
Do not send me any file format other than Inkscape SVG
Do not send me several revisions of the same file
Do not send me several files with individual pieces
Do not include text, symbols, dimensions or other labels in your drawing.
Do not include any filled regions in your drawing.