joannes has iron on label books- you can press them onto fabric- fill in the blanks with a permenent pen- the iron on transfers can be used more than once & they have a variety of labels, sizes, shapes, occassions to use. they are a good way to go.
as for minimum content- name of quilt, pattern if you used one- your name, city/state, date (at least month/year) fiber content---and i generally add care instructions.