Painting a metal closet door requires certain considerations. Brush strokes or roller marks are more likely to show on metal doors. Metal doors must be primed before being painted, using an appropriate product; most primers will not bond well. Take a few precautions to ensure that the paint will adhere properly and not flake off in time.
Use a screwdriver to remove the door from its hinges. Remove all hardware, such as knockers and door knobs. Set the hardware and hinges aside. Tape any screws to the hardware to keep them from being lost. Take the door to your work space.
Set the door against a wall or set it flat across sawhorses. Clean the door with a damp rag and soapy water. Allow the door to dry completely.
Sand the door on both sides with 120- to 150-grit sandpaper to create a rough surface to which the paint can adhere. Brush a dry cloth against the door to sweep away the grit.
Paint the broad side of the door with a layer of metal-etching primer. Use a paint roller for large flat areas and a paintbrush for panels and recessed areas. Allow the primer to dry.
Carefully turn the door over and apply the primer to the other side as well as the edges of the door. Wait for the primer to dry.
Paint the door with your chosen paint using a soft-bristled polyester brush. Wait for the paint to dry completely before applying a second coat.