Notch for beams
Cut 5½-inch-long by 1½-inch-deep notches in the tops of the posts. Lay out the site and dig holes for posts that form a rectangle
5 feet by 4 feet. Adjust the heights of the posts so the shoulders of the notches are level with each other. Tamp the soil
or temporarily brace the posts in position.
Cut the ends of the 2 by 6 beams to a decorative profile. Seat the beams in the post notches and center them from side to side. Bolt the beams to the posts with two 5-inch carriage bolts at each joint.
More: where to start and what you'll need