In short, an advance directive can enable you to make decisions about your future medical treatment. Most states have their own living will forms, each somewhat different. It may also be possible to complete and sign a preprinted living will form available in your own community, draw up your own form, or simply write a statement of your preferences for treatment. You may also wish to speak to an attorney or your physician to be certain you have completed the living will in a way that your wishes will be understood and followed. You can include instructions about any treatment you want or wish to avoid.
Some states have specific laws allowing a health care power of attorney and provide printed forms.
In some states, laws may make it better to have one or the other. There is no requirement for anyone to write an advance directive. The decision to write one or not to write one is entirely up to you. You may change or cancel these documents at any time in accordance with state law. Any change or cancellation should be written, signed, and dated in accordance with state law, and copies should be given to your doctor or to others to whom you may have given copies of the original.