A structural surface design device for creating a design with finishing surface material on a surface, the device having a base with raised projections on the bottom. Such projections have less of an affinity for the finishing surface material than does the surface on which such finishing surface material is to be applied. A handle extends upward from the base. And, optionally, the cross-sectional shape of the base is the same as the cross sectional shape of a container for the finishing surface material with the dimensions of the container and the base being such that the edge of the base, when the base has been inserted into the container, is sufficiently close to the wall or walls of the container that any finishing surface material in said container will not cure.