Step 1: Materials
-a needle threader
-2 pieces of cardstock (I used index cards here)
Step 2: Design the Template
Once your figure is drawn, make evenly spaced tick-marks on each edge. If you use a compass and straightedge, this is done by bisecting each segment three or more times.
Step 3: Poke Holes
Then, I prefer to do this on the edge of a desk, put the template on top of the blank piece of cardstock. Poke two of the three needles into corners of the triangle so that the pieces cannot rotate, and then use the third needle to punch the remaining holes on that side through the bottom sheet. When you finish a side, move the needles to the next side and continue.
Step 4: The Outline
(If you have an odd shape, it may take multiple pieces of thread and may not form a loop, but it's ok to just leave the ends taped as long as they're on the back.)