So I went searching for instructions on how to make them. Here's what I ended up doing.
Take a digital picture of your subject's profile, basically make sure you can see their ear. Print out the photos, and cut them out with small scissors (I started with large scissors and it was much harder to cut out all of the detailed parts).
At this point you can either trace your new stencil onto black paper and cut that out, or paint the original black. I couldn't find any black paper so I opted to paint. And I decided to flip the pictures over, I just like them facing the other way better.
As my kids say-- easy peasy lemon squeezy!