Just when I was thinking where to get base fabric from (which I need for the korak method), my husband offered me old bedcloth, enough for the rest of my life. And this is exactly what I need: Cheap and slightly worn-out cloth, no jersey, but woven cotton. The stiffness should be gone, and it should not be too good to be covered all over, not as stiff as normal quilting fabric.
It is ugly enough to be stamped or printed on and provides a basic pattern to work on with. It is stuff that has been used by someone I love -- I would find it difficult to incorporate something which comes from a person I don't know anything about; as for worn cloth, I have to trust a person to integrate material from her/him into my work.
