Attach a drawer face along the 10 1/2-inch side of the front of a drawer bottom. Attach the drawer sides on top of the drawer bottom, so they are flush with the top and sides of the drawer face. Attach the drawer back between the drawer sides. Use two 1-inch screws per attachment. Repeat twice more until you have three drawers, then attach the handles.
Attach the 14-inch by 2 1/2-inch boards to the 34 7/8-inch by 2 1/2-inch board, thus forming a "U," 34 7/8 inches long and 14 3/4-inches wide. Measure in from each 14-inch board 10 5/8-inches and attach each 13 3/4-inch by 2 1/2-inch board. Use two 2-inch screws near the center, 1/2-inch apart for each attachment.
Lay a 35 3/8-inch by 15 1/4-inch board on top of the assembly from step 2 so that there is a 1/4-inch overhang on all sides. Attach by placing a 2-inch screw every 3 inches. Flip the assembly over and repeat the process with the second 35 3/8-inch by 15 1/4-inch board.
Lay out the four 1-inch boards in a square on the 35 3/8-inch by 15 1/4-inch board, leaving a 1/4-inch margin around the outside of the square. Attach with 2-inch screws every 3 inches.
Drill holes in the centers of the 2 1/2-inch by 2 1/2-inch boards and install the tee nuts. Attach the boards inside the corners of the square from step 4 with four 1 1/4-inch screws each, so that the tee nuts are not visible.
Install the hanger bolts in the legs and screw them into the tee nut holes.
Set the desk on its legs and slide in the drawers.
Use the wood putty to cover any exposed screw heads before painting or staining the desk.