I could go and invest in a longer ruler, but nah! In this case of events I usually whip out my tailor's tape. I extend the tape from the waist marking to the hem marking. In the photos below I am connecting line #9.
While holding the tape in place with my left hand, I make a dashed line at one end, following the edge of the tailor's tape.
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[ drawing a couple dashed lines along the tape ] |
I then connect the dashed line with my ruler and pencil.
At this point, part of the pleat line is drawn in. My ruler now can complete the line.
So that's how I trace my patterns! It would, of course, be a lot quicker to use a tracing wheel and carbon paper (which I do use on modern patterns), but this is my tracing method of choice for the vintage ones. OK, off to sew!