Tell someone where you are going and when you plan to return.
Never go alone, and ALWAYS stay together!!!
A map and compass! Cell phones will only work so far. - Global Positioning Satellite Receivers (GPS) are great, but they become useless once the batteries are dead. Never rely totally on this technology, when you go out in the backcountry ALWAYS take a map and compass with you and make sure you know how to use it!!