Hi Nick
Ankle circles, point and flexes, and spelling out the alphabet with your foot are great ways to cause movement at the ankle in a gentle yet effective manner.
Danielle
Look into AIS stretching and call a Physical Therapist. There is really only one plane of motion that personal trainers should stretch concerning the ankle, the saggital plane(plantar flexion/dorsal flexion) any transverse or frontal plane mobility is best done by a medical professional.
Stop wearing shoes – They inhibit all the muscles and connective tissue from being strengthened as well as limit flexibility. I light being barefoot and prefer wearing Vibram Five Fingers when bare footing is not an option.