I drew the sign on paper the size that I needed it to be, and then traced the sign on white prepared for dyeing fabric. I used Tsukineko Inks to color in the sign. I then turned the edges under and stitched it to a piece of maroon wool. I cut the wool out to the shape of the sign and stitched it to the building.
The wool backing gives the sign some loft and makes it more prominent on the building. I have used this technique on small flags and other signs on quilts and like the effect of it. You can use felt in place of wool as a backer and save some money.
Think about using this on other features in an art quilt that you want to stand off the background a bit, such as leaves? flowers?