Just sniffing a strip of ribbon up your nose which is shocking enough..but then producing it from your mouth as a mini 'bow" that it transformed into. Although the one he used wasn't a good looking mini bow.
The nose and rubber band were subtle enough changes that I had to figure out what the illusion was supposed to be. The twirl didn't look like what came out of your mouth to the level that it kinda broke the illusion.
I suddenly remmembered about this final one string trick today and was thinking to search about it, but youtube itself showed me this today itself. What a coincident.