To prepare the silk, so the calligraphy letters won't spread, I apply a layer of Jacquard's No Flow mixed down with some water. Then, I thicken up the silk dye with some Pebeo Soie Thickener. I've got a template underneath the silk for placement of the letters (and so I don't forget any). I use a flat brush, creating thick strokes with a flat stroke, and thin lines with just the edge of the brush.
This Hebrew calligraphy is the traditional blessing said when one adorns a tallit, or Jewish Prayer Shawl: "Blessed are You O Lord, our God, King of the Universe Who has sanctified us with Your commandments and commanded us to wrap ourselves in tsitsit."
The calligraphy in the context of the almost-finished prayer shawl.