Clean the oven top with a dish detergent or soap with a degreasing agent, using a cloth. Let the surface air dry for about an hour, or wipe it thoroughly clean with a towel.
Sand the entire surface with sandpaper. Because an oven top is so smooth, paint is unlikely to stick unless you rough up the surface, giving the paint something to grip to.
Rub the appliance down with a tack cloth or damp rag to remove the dust particles created by sanding.
Lay a drop cloth on the floor beneath the oven and cover the adjacent countertops with newspaper. Tape newspaper to the front of the oven and on the wall behind the oven. This will protect the area surrounding the oven top from being painted by accident.
Shake a can of spray paint for at least one minute. Remove the cap and hold the can about 12 inches away from the oven and apply thin coats, moving the can from side to side. Keep the can in constant motion to avoid uneven coverage or drip marks.
Allow the first coat to dry for at least 10 minutes and then apply a second coat. Do not return the oven to regular use for at least 12 hours.