Begin with an assessment of their ability to control the musculature of the ankle with Tandem Stance, Blind Tandem Stance, Single Leg Stance, and Blind Single Leg Stance. Assessments are time to failure uninjured ankle vs injured ankle.
The higher the discrepancy the more low level neuromuscular re-ed exercises you should focus on. Also strengthen the Peroneals using bands and/or light cables. Also help facilitate their posterior talar glide.
As the stance tests improve begin phasing in performance exercises focusing of assisted lateral single leg movements.