6) To guard against cracks appearing in the countertop, cover seams with the mesh tape sold for use with cement board. The tape has an adhesive backing, so it stays in place.
7) With aviator's snips, cut 2½-pound galvanized-steel stucco lath to match the countertop, minus a 1-inch gap along all edges, including all around the sink. If you need multiple pieces, overlap the mesh by a few inches.
8) Tack a board 1 inch thick along the back edge to create a guide when you screed the concrete. Plan to cover this later with a backsplash.