permenent markers work, or print and heatset it from the printer, or embroidery, all have been used...matching fabric from quilt, i've actually written my label right on the back of a quilt; embroidered a block with all the info and incorporated it right into the front of the quilt, i tend to add my label before quilting so that it can not just be removed. include name of quilt, your name and whereabouts, the date, fabric content is always a good idea, including the type of batting, sometimes my labels are short, a couple lines, others have been a whole page, story...just put on a label!