To ensure you have the proper tools, take inventory of the various tasks you will need to perform when building shelter such as cutting, de-branching, notching, lashing, digging, and weaving. Consider what tools could help with these tasks (and all the better if one tool can address several tasks) and make sure they are in your bug-out and get-home bags as well as on your person while you’re out exploring.
First you'll need to find water. Water flows downhill, encourages vegetation, and collects in natural caches, be they ponds, lakes, rivers, springs, rock depressions, or even leaves. Unfortunately, most fresh water sources are not pure enough to drink from (as they used to be), so you'll need to know how to purify water under most situations. Use any of these methods to collect clean, purified water:
Imagine for a minute that you work downtown in a large city, maybe you ride the subway or take a bus to work everyday. You are in a large office building with many floors, thousands of people, and you are on the fifteen or twentieth story. If a disaster strikes how are you going to get out? I mean literally. If there is an earthquake, or a catastrophic man made event how are you going to get out of your building? How are you going to get down the street? How are you going to get home? Do you want to be one of the people covered in dust wandering around in shock? I sure don’t.