do you have heart problems or are you pregnant? im not sure it can be helped as sometimes its down to fluid build up, best speak to a doc
Of course you will need to work with your doctor on this. Elevating your feet above the level of your heart is one step you can take. Greatly limiting your salt intake is another. A prescribed potassium-sparing diuretic from your doctor could help. If you are in heart failure, you really need to follow a well-trained cardiologist's advice.
I have provided a link to information that may help you. If you have any questions after reading the information available, feel free to ask on the this thread and we will be happy to discuss the matter.
http://www.medhelp.org/tags/show/28524/ankle-swelling