Measure the width and height of the area where you'll be installing the wall. Cut two 2-by-2-inch boards to match the width of the wall. These are the top and bottom sills of the wall.
Cut one 2-by-2-inch board to match the height of the wall, less four inches, for every 16 inches of wall width, plus one. These are the vertical studs of the wall.
Place the top and bottom sills of the wall parallel to each other on the ground. Arrange the vertical studs perpendicularly between them, starting at one end, and spacing them 16 inches apart. Place the last stud even with the other end of the top and bottom sills. Nail the studs to the sills with 8d nails.
Raise the wall and place it in position. Nail the bottom sill to the subfloor every 16 inches, and to the ceiling joists where they intersect.
Cut panels of 1/2-inch plywood to fit onto the wall. Nail them to the vertical studs with 6d finishing nails where they overlap.