First intermediate ring
Add a second ring in the proximal fragment of the midshaft, connecting it with 4 rods to the proximal ring.
The distance of this third ring to the fracture will determine the working length. More length means more flexibility while a shorter length will give greater rigidity.
Insert 2 K-wires as perpendicular to each other as possible.
Using a Schanz screw will make the construct more rigid.