In reply to robcaesar: First thing would be to get an elastic bandage and wrap it around your ankle/foot. Then apply RICE: Rest, Ice (a few times a day, freeze water in a styrofoam cup and use that), Compression (the bandage), Elevation (if possible keep your foot higher than your chest level).
After a few days start doing the alphabet exercise (draw each letter of the alphabet on an imaginary board using your foot).