 above the average DIYers, but what I've done is I've found areas in the concrete that weren't that visible, like on the side or the bottom of a step or slightly below grade, and I've used a drill, a hammer drill, which is a masonry drill, and drilled out some test holes and collected the chips because that dust is the same color as the rest of the concrete, and then I sprinkle that over the caulk and tap it down with my fingers, and it blends in perfectly with the surrounding surface.