What safety measures would you advise someone to follow during a natural disaster

It would depend on what type of natural disaster. In case of a tornado or hurricane, you need to take shelter in a room (preferably a basement) away from all windows. If you have enough time you should evacuate to a safer location. The power may go out for days at a time, so try to have a portable charger for phones, food that won't expire, and plenty of drinking water.