Many doctors suggest using the RICE approach - Rest, Ice, Compression, Elevation--for treating ankle sprains (see the box below).
Rest - You may need to rest your ankle, either completely or partly, depending on how serious your sprain is. Use crutches for as long as it hurts you to stand on your foot.
Ice - Using ice packs, ice slush baths or ice massages can decrease the swelling, pain, bruising and muscle spasms. Keep using ice for up to 3 days after the injury.
Compression - Wrapping your ankle may be the best way to avoid swelling and bruising. You'll probably need to keep your ankle wrapped for 1 or 2 days after the injury and perhaps for up to a week or more.
Elevation - Raising your ankle to or above the level of your heart will help prevent the swelling from getting worse and will help reduce bruising. Try to keep your ankle elevated for about 2 to 3 hours a day if possible.