You can get a free copy of an advance care directive at:
If you have medical insurance, your HMO will have a form you can fill out and put in your medical record. They might even recommend it just before you have surgery. And if you are anticipating surgery and it has been awhile since you filled one out, it could be worthwhile to look at it again and be sure what you wrote is still what you want.
When you complete such a living will you will want to:
name another individual as agent to make health care decisions for you
give specific instructions about any aspect of your health care, whether or not you appoint an agent
You can revoke the advance health care directive or replace it at any time.”
Decisions you can make include prolonging or not prolonging life, relief from pain, organ donation.
NOLO Press has thousands of free articles on law at http://www.nolo.com/legal-encyclopedia
scroll down to wills, trusts and probate / estate planning
or, if they still have the section,
Making a Living Trust: Can You Do It Yourself?