What is the best way for decoupaging curved surfaces and corners?

Curved Surfaces:
To apply a flat print to a curved surface, cut slits in the paper wherever it will buckle. Let the paper on each side of the slits overlap as you carefully conform the print to the curved surface.

Corners:
Before applying glue, fold the print around the corners of the project surface as you would wrap a package, creasing along the edges to mark them on the print. Rather than overlapping the paper as if wrapping a package, cut away excess paper. The new edges of the paper will meet at the corner.