This kit, and a little knowledge will most likely get you out of most survival situations.
Step 1: Starting out
So the tin here is a tobacco tin, its pretty watertight and can be used to boil water in. as well as cooking small meals.
Step 2: Water
I added a large ziplock bag, water purification tablets, and of course the tin can be used to boil water to disinfect it
Step 3: Fire
Simple kit containing ferro rod and striker, matches, cotton wool and home made tinder straws (wax impregnated cotton wool, burns like a candle for a couple of minutes, lights from a spark)
Step 4: Tools
a short hacksaw blade section, a wire saw and a small multitool.
I then added a whistle and compass for navigation and signalling, plus the lid of the tin is reflective enough to be used as a signal mirror.
Step 5: Repairs
a small sewing kit, some electrical tape (good stuff), sandpaper to keep the knife sharp and some inner tube bands multiple uses.
Step 6: Food
A small fishing kit (hooks, sinkers, line and swivels) and some snare wire (can also be used for lashing)