Ankle stiffness after cast removal.

Hi I had sprained my ankle of my left leg.So a cast was put up by the doctor for 10 days but after removing the cast the area below and above ankle as well surrounding area of ankle has become quite stiff. There skin has turned reddish blueish and blackish. Though I can just put my weight on the ankle but still cannot walk as it pains and it quite stiff to bear the weight. How do I reduce the stiffness so that I can walk ? Also wanted to ask does icing or warm water which should I prefer for healthy blood flow to the ankle area? My ankle does not bend near the front area when I sit on chair so what stretching exercise should I prefer? I have attached the image of my ankle area as well for more information. Please suggest some measures to my questions. It would be a great help.