Clean the cement or concrete wall with a power washer to remove debris or paint. The concrete surface needs to be clean for the mortar to bond.
Attach the metal lath to the concrete surface with a high voltage cordless drill and concrete fasteners or screws. Install a fastener in each corner and along the outside edges in the center of the lath.
Prepare the mortar according to the manufacturer’s instructions. Apply a 1/2-layer of mortar to the metal lath with the trowel. Press the mortar fully into the screen.
Let the mortar set until it is almost dry. Press your thumb into the mortar; if you leave a print, you can score the mortar. Score the mortar by dragging the notched edge of the trowel across the mortar in horizontal lines.
Spray the etched mortar with water to moisten the surface. Use only enough to moisten the mortar.
Add a half-inch of mortar to the backside of the masonry veneer. Press the veneer to the etched surface on the cement beginning at the top right corner. Work your way across and down in this manner until you cover the entire surface with the masonry veneer.
Dip the corner of the trowel into the mortar. Spread the mortar over the joints between the veneers. After you grout the entire veneer surface, let the grout set until scrape excess mortar from the bricks with the clean edge of the trowel.
Brush away dried mortar from the surface with a soft bristle brush.