The foot is elevated and cleaned.
The sole is filled with plaster of Paris to develop an even footing surface followed by applying one role of fiber glass cast material around the hoof capsule.
Once the cast has set the horse can place weight on it again. The sole of the cast is protected by hoof acrylic to prevent rapid wear.
Another alternative is to apply a bar shoe with side clips. Ideally, the sole is filled as described above.