Installing No miter/no cope crown molding
Install the inside and outside corner blocks. Make sure they are square. Apply adhesive latex caulk. Align and screw blocks in place with trim head screws.
Cross-cut the molding to length. Measure the distance between corner blocks. Mark the straight molding across the face with a pencil and adjustable combination square. Cut the molding on a power miter saw or by hand in a miter box.
Install the molding. apply a bead of latex adhesive caulk to the edge of the molding that will contact the ceiling and wall. Once in place, snug it into position to equally contact the wall and ceiling. Then drive trim-head screws through the molding and in the the wall studs and ceiling joists. Clean away excess caulk. Fill gaps along the wall and ceiling with latex caulk, fill the screw holes with glazing putty and paint the molding.