This looks like the trip of a lifetime.  It was organized by Deb Roberts and World of Quilts Travel.  Kim, an expert quilter, not only learned how to batik but also waded into the Indian Ocean, sampled a lot of spicy food and enjoyed lots of massages, including one where the masseuse climbed on her back!  According to Kim, if I understood her correctly, the way to make batik is to outline an image on muslin with melted wax.  After the wax dries, you paint the image.  Then, the fabric is washed in a special solution which removes the wax.  I’m sure my explanation is a gross over-simplification, but Kim and Julie clearly mastered the technique in their short time there.