Lay the 60-inch boards on edge, parallel, and 45 inches apart. Place the 45-inch boards between them so they are on edge, perpendicular to the 60-inch boards, and 57 inches apart. Screw through the 60-inch boards into the ends of the 45-inch boards so you have a 48-inch-by-60-inch frame. Use your 3-inch screws for this process.
Position a 31-inch board in each corner so the ends are flush with edges of the frame. These are the legs to your table. Screw through the boards on the frame at each corner and into the legs. Position your table upright so the frame is on top, standing on all four legs
Use your 2-inch screws to screw your eight 72-inch boards to your table frame. There should be a 6-inch over hang at both 48-inch ends of the table. The two outside 72-inch boards should be parallel and flush with the 60-inch boards on the frame.
Screw your last two 45-inch boards to the table legs, one on each 48-inch side of the table. The 45-inch board should be positioned so it is between both sets of legs, and so it is 20-inches below the 45-inch board on the opposite side. Screw through the 22 1/2-inch center of both of these 45-inch boards towards the center of the table, into the 40-inch board. This board will provide support for your table.
Sand down the table with your medium and fine grade sand paper. Wipe the table down with your tack cloth, apply the wood stain, and let the table dry.