um... you can just have it as a texture.. place it.. scale it whatever and remap the color so the background of the logo matches the main shader color.. but if. A stencil can do it but i find if i just want a logo on my surface i just remap the color of the logo to want (find that under the effects section of the file texture node) then if you want other textures on it you can add a texture to the default color or bake the surface as a texture then add from there.