Determine the direction of the floor joists. Look at the nail pattern in the subfloor to help you figure out which way the floor joists lie. For example, if the nails are in a horizontal line from east to west, the floor joist is installed in that direction.
Find a long, straight wall that is perpendicular to the direction of the floor joists. The wall should have no obstructions. If there is any shoe molding nailed into the wall, remove it with a pry bar.
Place a spacer block in the corner of the selected wall.
Lay the first wood plank along this wall. Lay the plank perpendicular to the floor joists with the grooved end of the plank against the spacer block and the tongue of the plank facing out.