Incapacity (and need for a surrogate decision maker) is most likely to be caused by cognitive impairment, as opposed to a physical injury. This surrogate decision maker, often a family member, will have to make a large number of decisions about a range of issues. (Housing, medical treatment and eating preferences, for example.) You can assist them by providing clear written instructions regarding where you want to live and how you want to be cared for when you can no longer communicate your wishes. For example, whether you would prefer to stay at home with assistance or move in with a relative. If your condition makes those choices unavailable, then what facility you prefer.
Your plan for future care lets your caregivers know who you are and what you like. It addresses major issues, like preferences in medical treatment and living arrangements. It should also cover details like a list of favorites foods, music, books, movies, TV shows and recreational activities.
This section should also include your preferences for your final arrangements. Some examples would include any pre-payment arrangements, whether you want to be buried or cremated, service / readings and who to invite.