Overview
Arden Wood, the Christian Science nursing facility in San Francisco, provides forms and sound advice for California residents to draw on when thinking about and creating legal documents such as advance health directives and proxies. Scroll down this web page until you reach the advance directives section where you'll find a list of guidelines and a sample AHCD.
The general information is useful for anyone, but the guidelines and AHCD draft were designed for California residents. Each state has its own laws and guidelines relating to advanced directives, so you should do research to determine the specifics of how yours should be written. And of course, attorneys are available who specialize in this area.