Cover the Ten Essential Groups for safety. In a life-threatening emergency it is important to have enough gear to remain healthy/stable (Medical), dry (Shelter), warm (Fire) and hydrated (Hydration) until rescued (Communication), if needed.
1. Medical- ID/medical tag, first aid kit, medications, insect repellant
2. Shelter- raingear, garbage bags, emergency blanket, bivy sack, tarp, tent, rope
3. Fire- matches, lighter, sparker/tinder, fresnel lens, stove/fuel
4. Hydration- water container, purification method
5. Communication- safety plan, whistle, pen/pencil and paper, signal mirror, cellular phone, satellite phone, HAM radio, personal locator beacon
6. Navigation- map, compass, light, altimeter, GPS
7. Nutrition- extra food, fishing kit
8. Insulation- jacket, hat, gloves, footwear, foam pad
9. Sun Protection- sunscreen, sunglasses, wide-brimmed hat
10. Tools- knife, repair kit, wristwatch, bandana
http://texas.sierraclub.org/dallas/page.asp?10essentialgroups
https://itunes.apple.com/us/app/take-ten-to-greater-outdoors/id412088534?mt=8