Wait several minutes or hours according to the direction of the can of the primer. The drying time of latex primer of metal garage doors will be about one hour. But it can vary greatly based on the brand, humidity and temperature. Apply the latex paint in the same overpowers as the primer. Latex paint in precisely the same manner as primer. Wait until the paint is dry, according to the drying time on the box, and apply a second coat, if you want.
These just if your galvanized metal garage door is old, rough surface of the door with a wire brush. Go over the door until all the white rust is removed. Clean the garage metal doors surface with a water-based cleaner and a sponge. Next, clean garage door surface with a water-based cleaner and a sponge. Wait for the surface to dry before continuing.
Dampen the cloth with white vinegar and scrub down the entire surface of the garage door. Apply vinegar to the cloth. Apply the primer on the garage door, by means of long strokes. Continue until the entire door is coated in primer. Wait quite a few minutes or hour According to the direction on the can of primer.