Make an outside miter cut on the last piece of crown molding. Do not nail the last piece of crown molding into place until you have done this. Measure how long the last piece needs to be. Make an outside miter cut to length by setting the miter saw to 45 degrees. Place the crown molding into place upside down. The molding’s bottom edge should sit against the fence of the saw and the other edge should rest against the table. Carefully make the cut.
Nail the last piece of crown molding into place on the wall with finish nails.
Cut an outside miter at a 45-degree angle on a scrap piece of molding. The scrap should be at least one foot long.
Make the wedge-shaped cap by setting the miter saw for a 90-degree angle. Place the scrap molding flat on the saw. Cut the piece so that it comes to a point at the bottom edge.
Glue the cap into place instead of nailing it. Nailing the small piece might split it. Use caulk to fill in any holes on the crown molding.