If you are 18 years or more, appoint another person to make decisions for you if you are no longer able to make your own decisions. Choose a person who knows you well and you trust to make decisions based on your wishes and best interests. This can help to avoid conflict between family members and healthcare professionals.
The law varies depending on where you live in Australia. There are two kinds of decision-makers; Enduring Power of Attorney and Medical Enduring Power of Attorney.