Business signs with a total sign area per establishment not to exceed 10% of the sign wall area and in no event more than 18 square feet; such signs shall be set back from the street not less than five feet. For any business use conducted primarily in the open, such as a parking lot, boat storage or similar use, the total sign area shall not be more than one square foot for each foot of plot frontage, not to exceed 18 square feet. However, in no case shall the area of any one sign exceed 12 square feet. In addition, a sign consisting only of the name of the establishment painted directly on an awning, with a sign area not to exceed six square feet, is permitted. All lights shall be directed away from adjacent residences.