The Kindling Cracker comes out of the box fully assembled, just needing to be attached to a sturdy surface. We picked this somewhat oversized log so we can place the sledge hammer on the log too.
Top view: place wood in the circle & start tapping. Within 2-3 taps. We had that sliver split. The flare acts like a wedge to help split the wood. We used only two pieces of wood from that stack, and made quite a bundle of kindling.