Sit on a step or low box, preferably with a back support. Extend both legs and wrap the band around the balls of the working foot
Pass the band around the other foot as shown in the video. Hold the end of the band with the opposite arm of the working foot
The ankle should be at 90° and turned inwards (inversion) before you start the movement. Turn the ankle out, without moving the rest of the leg.
Eversions Exercise Guide - Feet Workout | MuscleWiki