If an individual rolled his/her ankle, it is important to focus on how to control the swelling. There are first aid measures that you can learn in a first aid course on how to properly ice an injured ankle.
Using a wet elastic wrap
With a wet elastic wrap or ace bandage, wrap it around the affected foot starting at the base of the toes and spiral up around the ankle and the leg. Tightly wrap near the toes and gently while working up the leg. Pinch lightly the nail on one of the toes using your thumb and index finger. The nail color will disappear but if it does not return within a few seconds, the wrap is too tight.
Take note that the application of the wet layer will improve the conductivity of the ice bag while at the same time help prevent freezer burn on the skin. The ice bag must be placed over the base layer and then wrap using a dry layer to secure the ice bag in place and create compression on the affected ankle.
Using the classic bag
A standard sandwich bag that most people use works well. All you have to do is to fill it with crushed, flaked or pellet ice to ideally conform to the affected foot. Allow enough space to tie the bag and make sure to remove air to improve the conformity as well as keeping the temperature consistent around the ankle.
Position the bag over the affected area and an elastic wrap around the bag, foot and ankle for compression. Along with the application of ice, the affected area must also be elevated higher than the heart for 20-30 minute sessions several times in a day during the initial 24-72 hours after the injury was sustained.
Alternative ice bags for an injured ankle
You can use a slush pack as an alternative to an ice bag which is a combination of water and rubbing alcohol. The advantage with this alternative is the comfort it provides and can easily conform to the foot unlike with the regular ice bags. All you have to do is to combine a cup of rubbing alcohol and 3 cups of water and pour in a Ziploc bag. Prevent spillage by placing into another bag and store in the freezer overnight.
These packs are considered convenient since they instantly cool without requiring a freezer anymore. The cold is generated as a by-product of the chemical reaction within the pack. The drawbacks of a chemical pack include a possible chemical burn if it leaks, varying temperatures and cannot be reused. If you are going to use one, always follow the directions on the packaging.
Water and gel sheets
You can easily find water and gel sheets at drugstores. These can be stored in the freezer and inserted into prefabricated wraps. When using one, it is quite similar as ice bags where you have to apply 20-30 minutes with elevation. These can be stored back in the freezer and reused.