Using an 8-foot aluminum straightedge, the author checks the plywood subfloor for flatness. Any low spots will telegraph into the flooring. This particular spot isn't low enough to warrant repair.
According to this pin-type moisture meter, the moisture content of both the flooring and the subfloor is 8%, acceptable for a New England summer.
The author walks on the floor and listens for squeaks; as he finds them, he marks them with an "X" to be addressed before the flooring goes down.
After locating and marking the floor joists, the author drives special screw-nails through the subfloor and into the joists.
The recently painted baseboard stayed in place for this project, so the flooring butted against it. Before starting, the author lightly marked the joist locations on the baseboard for secure nailing.
After checking the walls for parallel, the author stretches a string along the "beginning" wall. A simple piece of wood with the distance marked on it becomes a gauge for judging how straight the wall is and for finding the farthest point from the string.
A straightedge screwed to the floor will keep the starter course straight as it's being scribed to the wall. A notched stick helps place the straightedge precisely parallel to the string.
The flooring strips for the starter course must be perfectly straight. The author sights down enough pieces for the first row.
The first course is cut to length and set against the straightedge; then, a scrap piece of flooring is used to mark the scribe line. (Note: Some folks have expressed concern here that the author is installing the new flooring tight to the wall. He addresses this concern in this Q&A.)
A track saw with the blade set at a slight angle cuts close to the scribe line. The saw's dust collection system minimizes the mess in the finished room.
The quickest and most accurate way to cut to the scribe line is with a hand plane. The angled cut from the saw makes this a quick operation.
Glue down the first course
A nail spinner (in the drill on the floor) drives the flooring nails part-way. A hammer finishes driving them; each nail is set flush with the tongue.
Fairly new on the market, a palm nailer designed specifically to drive cleat nails for wood flooring is much faster than hand nailing.
To protect the finished surface of the flooring, author uses a scrap block to tap a strip snugly against the neighboring board.
Felt paper slows down any water vapor and adheres the flooring to the subfloor to minimize movement. Use of 15-lb. felt is often required by the flooring manufacturers.
While one of the crew nails off the first courses, another "racks" the boards to be installed. Boards are placed on the floor with seams staggered the proper amount. The installer can then just pull the boards over with his feet and nail them into place.
At the end of the floor, the person racking lays the final pieces upside down and backward.