I won't get into an explanation of the craft here, there are plenty of sources online for that, and you could easily spend an entire day trolling Pinterest looking at images like this one:
The pin doesn't take you directly to the post for this image, so I'm not including it, but here's the link to the Keeper of Tradition blog article, Falling Between the Cracks:
As the great migration continues, I have two Helium articles related to this topic to share. The first, which you'll find below, is about where to find Scherenschnitte patterns online. The second is a book review of The Paper Cut-Out Design Book, a wonderful resource on traditional papercuts, by Ramona Jablonski.
Originally published in July of 2010, here it is...
Where to Find Scherenschnitte Patterns Online
My papercraft pinboard: For the Love of Paper