Set the copper drip edge on the bottom edge of the roof. Secure with the copper nails. The drip edge helps ensure that water falls down off the roof instead of seeping under the roof edge.
Roll the roofing felt out across the roof sheathing. Attach the felt to the sheathing with copper nails or as directed by the tile manufacturer. Some manufacturers make use of underlayment and some do not.
Attach copper flashing with copper nails at every location where the roof meets a wall, chimney or skylight. The flashing helps to seal the joints against leaks. If it sticks up out of the roof, or is an area where two sections of the roof join together in a valley, it needs flashing. Also install the ridge flashing over the ridge, or peak, of the roof.
Install the wood battens. There is one row of battens for every row of tile. Since tiles come in a variety of sizes, the number of rows you need will depend on the type of tile purchased. The battens are what the tiles attach to during installation.
Lay the first row of tiles, beginning at the bottom edge of the roof. Nail or screw the tiles to the battens as directed by the manufacturer. Overlap the first row of tiles with the second row and secure the second row into place. Each tile maker has a preferred amount of overlay. Keep laying rows of tiles until the roof is covered.
Finish off the roof by covering the ridge. Mix mortar in a bucket and trowel the mortar onto the ridge line of the roof. Set tiles onto the mortar, overlapping them as you did when setting rows.