A tip from the backpacker Sierra Mountains from California.
Here are some essential tools that I take on every backpacking trip and have served me well.
First is 3-4ft of 3/8″ surgical tubing, which can be used for making a slingshot, bow and arrow, emergency tourniquet, and snares. Best use is making a spear out of long straight wood and making slingshot to spear fish in shallow water.
Second is a dozen black 8″ long zip-ties, which have many uses.
Third is black high heat duct tape, wrapped around a lighter (thank you for a great idea, Dirty).
And last but not least, parachute cord wrapped around plastic water bottle to protect it from impacts and damage, and keep water cool during heat.