Your advocate can make sure that your doctor's orders are followed regarding having leg wraps to reduce your risk of blood clots; a breathing exerciser to reduce the risk of pneumonia; as well as your bed elevated per doctor orders.
If you have any allergies, it might be a good idea to post a sign over your bed stating them.
I'm sure you've heard the old adage, "If you want to get sick, just go to a hospital." To prevent the spread of infection, be sure everyone coming into your room washes their hands.
Be sure you meet with a physical therapist before you leave the hospital. Physical therapists are able to demonstrate to you the best way to get in and out of bed; in and out of chairs; walk up and down a limited number of stairs, etc. You may also get a few exercises to start with before your physical therapy begins at home.
Lastly, it is important to have completed a medical power of attorney. If you should become unable to speak for yourself, the person you name will have the right to speak for you. Be sure you make your wishes clear to your representative.
There is also something you should do even if you are not going to the hospital: Make a list of all your medications and supplements and keep it in your wallet. That way, if an emergency happens, the paramedics will be able to give your list to the emergency room when you are brought there.