I second John’s tip. My computer is an invaluable aid to me. I have
all my sketches scanned, and I can scan the stones and work on the
designs on the computer. Being able to size things precisely is a
wonderful thing. And since much of my work involves layers of
piercing, I can put different design elements on different layers and
reshape and resize everything separately. Duplicate all the elements
so I have the complete design for reference plus all the elements
separately , print the whole thing out, and glue it down on the metal.