Surviving is all about making your body happy in the adverse conditions that it is forced to endure.  In our current society you are comfortable, well fed, and have a warm place to sleep.  In a survival state all of the support structure that provides the  life lines for you will be destroyed or broken and you will need to provide for yourself.  In the current state this would happen if you are lost in the woods or in an accident that separated you from your society.  When you are lost you are surviving to get back to civilization and be rescued.  When the SHTF you are in a completely different situation.  You may not want to be found, you may not be able to use fire or travel because the entire society is now in a survival state.

Priority based on your bodies needs:

• Blood – Apply fist aid to wounds where you are loosing blood
• Air – Place your nose and mouth in a protected place to ensure you can breathe and do not have  issues due to water, smoke, particulates or pathogens.
• Temperature – Keep your body the perfect temperature and protect it from exposure to the elements.
• Water – Clean filtered water free from toxins and pathogens.  Water is heavy and difficult to keep as much as you need.
• Food – High calorie nutritious food will be rare and very valuable.  It will be a non renewable consumable that will run out quickly.