Where two pieces of trim meet at an inside corner, you may be tempted to cut each at a 45-degree bevel and butt them together. Unfortunately, this method often results in unsightly gaps. Instead, pros use a coped joint, which seems difficult at first but is actually fairly quick and easy once you get the hang of it. Use coped joints for baseboard, chair rail, crown molding, and anywhere else two pieces of trim meet at an inside corner.

To start, cut the first piece of trim at a 90-degree angle, butt it tightly into a corner, and nail it into place. For the next piece, which will be cope cut, use a board that is longer than needed; you will cut it to length after making the coped joint.

The next steps don’t seem as if they will work, but they will. Use a power miter saw or a hand miter box to cut the second piece at a 45-degree bevel, with the back of the trim longer than the face.

The face of the trim end now has a profile that will follow the contours of the trim piece already installed; you just have to cut away the back portion. To emphasize the line of the curved cut you will make, run the side of a pencil along the edge.

Use a coping saw, which has a very thin blade that allows you to cut tight curves, to cut along the line. Hold the saw blade at slightly more than a 90-degree angle to the face of the trim so you cut off a bit more of the backside than you need to.

Test the fit; it should be tight all along the profile. If not, you may need to cut away some of the back of the trim using a utility knife. Work carefully to avoid splintering the end of the board.

Hold the cope-cut piece in place and mark it for cutting to length at the other end. Then nail it into place.