Decide which cardinal direction the entrance of the birdhouse will face. Most birdhouse entrances face east, to let in the morning sun and avoid afternoon glare, but regional weather patterns should be the deciding factor in choosing the entrance direction.
Drill two 5/16 inch holes in the back of the metal pole and the birdhouse, making sure the holes in the pole and birdhouse align.
Insert 1/4 inch stove bolts first through the holes in the birdhouse and then the pole to anchor the birdhouse to the pole. Lightly shake the birdhouse to ensure it is secure and cannot be toppled by wind.
Install, if desired, a cone pole guard (also called a baffle) to further protect the birdhouse from predators. Metal or plastic baffles can be purchased at many pet stores and come with instructions and the necessary installation equipment. If making a baffle at home, purchase a 24 or 26-gauge galvanized sheet metal circle 3 feet in diameter. Cut 1 1/2 feet toward the center of the circle than wrap it around the pole under the birdhouse so the two ends of the metal overlap to form an inverted funnel. Drill three 5/16 inch evenly spaced vertical holes through the overlapping ends and insert 3 1/4 stove bolts through the metal to secure the baffle.