Quick one evening project. Actually two evenings since I had to wait for the decals to dry!
I started with the post from a JL Innovative gas station detail set. (This same set included the Esso gas pumps). I first painted the sign post flat white. Then I painted a piece of thin (.005") styrene dark blue and then applied Microscale Esso decals to the styrene. I snuggled the decals in place with Solvaset and let them dry. Once they were dry I carefully trimmed around the edges of the decal, flipped the sign over and applied a second Esso decal sign to the opposite side. I allowed the decals to dry completely overnight.
I rusted the edges of the sign and the post with Raw Umber and Mississippi Mud acrylic paints applied sparingly with a piece of torn sea sponge. I got this technique for rusting signs watching Jason Jensen's YouTube channel.
I fabricated the crossarm for the sign from pieces of brass wire.
The base is basswood coated with Ceramic Stucco to give it a little concrete texture. I painted it with light tan acrylic paint and weathered it with some rust colored chalks.