Keep it informal. A certain informality defines cottage garden plants, of course, but it also applies to your hardscape. Gravel, pebbles or bark make great choices for paths, for instance. Rather than identical bricks set precisely in mortar, look for discolored older bricks with a few chipped edges, and set them so that the space isn't precisely even between each paver. Stepping stones also give a cottagey look. Local materials are the best choice if you can find them.
Design tip: While imperfections in a walkway look charming, get the effect by varying the width between different pavers and keep the actual walking surface even. No one wants to trip over an uneven stone, especially at night.