Measure the room and calculate the total length of crown moulding needed
Purchase crown moulding, corner blocks if desired, adhesive, nails, caulk, wood filler, and paint or stain
Gather tools including a miter saw, tape measure, stud finder, level, nail gun or hammer, coping saw, caulk gun, and safety gear
Locate and mark wall studs and ceiling joists
Determine the spring angle and installation orientation of the moulding
Cut test pieces to confirm the correct miter and bevel angles
Measure each wall section carefully
Cut inside and outside corners using miter or coping cuts as needed
Dry-fit each piece before fastening
Apply construction adhesive to the back of the moulding if desired
Position the moulding tightly against the wall and ceiling
Nail the moulding into studs and ceiling framing
Join longer runs with scarf joints where needed
Fill nail holes, seams, and gaps with wood filler and caulk
Sand filled areas smooth after drying
Prime and paint or stain the moulding as needed