Set two 53-inch boards parallel on edge and 23 inches apart. Set two 23-inch boards between them on edge so the pairs are perpendicular. Space the 23-inch boards 50 inches apart so their sides are flush with the ends of the 53-inch boards. Screw through the 53-inch boards and into the ends of the 23-inch boards. Use 12 screws for this task. This is your sheep bar frame.
Lay your wire wire mesh on top of the frame so all the edges are flush. Attach the mesh to the frame by pounding staples through the mesh and into edges of the boards on the frame. Use all 16 staples.
Position the frame on edge so it is lying flat on one of the 53-inch boards. Lay a 27-inch board perpendicularly against the frame so its end is flush with the edges of the frame opposite the side with the mesh. The board's side should be against the side of the 23-inch board and the end of the 53-inch board. Screw through the 23-inch board and into the 27-inch board using three screws. Repeat this process on the other end of the frame. These are two legs to your sheep bar.
Turn the frame over so it rests on the other 53-inch board. Follow the same process in the previous step to secure the last two legs.