Start the installation at the longest unobstructed wall. Remove the shoe molding, and snap a chalk line 3/8" out from the baseboard. This allows for expansion in hot, humid weather, and contraction in cold, dry weather. Read More 
Place the Boards
Begin by selecting a long board to start the first row. Pick one that is straight. Align the edge of the board with the chalk line.
Hand-Nail / Staple down (In case of Nail down installation)
After the first few rows have been installed, drill pilot holes down into the tongue of each board and hand-nail the rolls until there is enough clearance for the pneumatic nail gun. Or, using the pneumatic nail gun, staple the board by striking firmly with the mallet, driving the staple into the tongue of the hardwood plank.
Cutting the Baseboard
When cutting along the baseboards, select a piece that will fit in there and leave 10 or 12 inches more and cut it off. Use the other piece on the beginning of the next row.
Fill in the Gaps
Be aware of the way the ends fit together. One end has a tongue and the other end has a groove. This is called end matched. Make sure to always cut the wall end of the wood so that you do not cut off the groove that fits to the tongue. If that happens, that would result in a pretty big gap. Find a piece and lay it alongside the hole and flip it over. Make sure when you make the mark to cut off the wall side, not the room side. When you make the mark, butt it up against the baseboard and then mark at the end of that tongue.
Work Around Clearance Issue
As you approach the opposite wall, there will be limited clearance for the pneumatic gun. Drill pilot holes and hand-nail the boards until there is no longer clearance for the drill and hammer. At that point, drill pilot holes down into the top of the boards and face-nail the boards, remembering to set the nails with a nail-set. (in case of nail / staple down installation)
Fit Last Board Into Place.
If there's a narrow gap for the last board, take a measurement and rip (cut length-wise) the last board to fit into place. Remember to leave a 3/8 inch gap at the end wall for expansion and contraction space.