Plan Ahead - Don’t Panic
Try to stay in your fallout shelter for a few days at minimum. Then you can venture outside for a few quick minutes to answer calls of nature. You will absorb some radiation, but not enough to kill you.
The radiation will continue to decay, hopefully down to levels that are livable, but check your civil defense announcements.
Learn to recognize and locate facilities that could be used as good emergency and long term fallout shelters.
Have stocks of bottled water in your car, your home, your place of work.
Always have a working flashlight and battery powered radio.
Learn something about your local civil defense facilities.