How do I apply the digital signature (Adobe.PPKLite)?

I'm trying to fill out a complaint form to send to the North Carolina DMV. I have to send the form electronically as I have electronic format evidence (texts, facebook conversations, etc.) that i have to send with it. They require the Adobe.PPKLite format for the digital signature and I'm confused on how to use it. Link to the form I'm trying to fill out is below.

http://www.ncdot.gov/dmv/licensetheft/default.html#vehicletheft