In reply to thecliff:
I can't claim to be an expert but I have sprained a few ankles...
Top tip:
Don't sprain your ankle at the Foundry, hop to the pub. Hop (with the aid of a walking pole) upto High Neb the next day to go soloing, then go on a 10 day sport climbing trip to Bourgogne unless you are comfortable with being told you are a pillock by an orthopaedic surgeon and spending several months in physio followed by 7 years of your ankle randomly collapsing under you
Do less exercise than you think you should, for a few weeks. Take some NSAIDs but don't use them as a crutch, if it twinges stop doing it. When you are feeling better do some low impact exercise:
Stand on your good leg, balance for as long as possible.
Stand on your bad leg, feel happy if you can manage half the time.
When your bad leg is feeling better close your eyes, this is harder than you think
Get a wobble board or similar and once you feel better do lots of exercise to build ankle stability and co-ordination, like walking on rough ground etc.
Best of luck.