A broken wrist often results from an accidental fall, as your natural instinct is to try to use an arm to brace yourself against the impact. This type of injury requires treatment from a trained medical professional who knows how to properly set the bone. You can take at home to help prevent the injury from worsening while you await treatment, as well as to speed your recovery.
If the break is severe enough to drive the end of the fractured bone through the skin, take steps to stop the bleeding. If you have access to a first aid kit, cover the wound with a large, sterile bandage. Otherwise, use a clean washcloth or, if necessary, a clean article of clothing as a makeshift bandage. Apply pressure to the injured area and keep the wrist elevated above the heart. Resist the temptation to try to push the bone back into place; it's best to leave that step to a trained medical professional.
Depending on the circumstances, it may take time before you are able to receive treatment for your injury. In the interim, do what you can to keep your hand and wrist immobilized. You may have the materials to make a rudimentary splint. One option is to wrap the wrist in newspaper, magazines or bath towels and use strips of cloth to secure the ends of the splint in place; padding the splint will help to reduce the pain. Once you've applied the splint, use a bandanna or a large piece of cloth to create a sling to hold the wrist against your chest.
An ice pack can help to reduce the swelling and numb the pain around the injured area. To create one, fill a plastic bag with ice cubes and wrap the bag with a towel; it's important that the ice does not come into direct contact with the skin or else it may cause additional damage. If you do not have ice available, substitute a closed bag of frozen fruit or vegetables.
Once your wrist is fully healed and the doctor has removed the cast, spend time rehabilitating the muscles in your wrist and hand, which will have atrophied from the extended period of inactivity. Sports and health care stores sell products designed to strengthen the forearm, including squeezable putties, rubber balls and spring-loaded grip exercisers. You may also wish to wear a temporary wrist support for a time after the cast's removal until you have regained your strength.