Remove or cover hardware, and protect surrounding surfaces with drop cloths and painter’s tape
Clean the door thoroughly with soap and water or a degreaser
Rinse and let the door dry completely
Sand the surface lightly to remove gloss and improve adhesion
Remove all dust with a tack cloth or damp microfiber cloth
Repair dents, scratches, or rust with filler or rust treatment as needed
Sand repaired areas smooth and clean again
Apply a metal-appropriate primer in thin, even coats
Let the primer dry fully according to the label
Lightly sand the primed surface if needed and remove dust
Apply the first coat of exterior metal paint with a brush, roller, or sprayer
Let the first coat dry fully
Apply a second coat for even coverage and durability
Allow the final coat to cure completely before closing the door or reinstalling hardware
Reattach hardware and remove protective coverings
Inspect for missed spots and touch up if needed