Making your own lets you adjust its contents to your climate, budget and situations. I hope people will take the kit I've put together as a base to start their own.
Lets get started...
Step 1: Assembling the contents
1.) Jumper cables (aka booster cables)
2.) Multi-Tool (one of those pliers that have tons of tools in the handle)
3.) Map (local area or area you'll be traveling)
4.) First-aid kit
7.) Duct tape (because you can fix a lot of things with Duct tape)
8.) Rain coat (the folded $1 type)
9.) Emergency blanket (the folded $1 type)
10.) Folding shovel (entrenching tool)
11.) Fuses for fuse box
12.) Water bottles
13.) Protein bars or M.R.E. (meal-ready-to-eat)
14.) Reflective tape or reflective triangles (flares are hard to find)
15.) Old Cell phone, fully charged. Call customer service via the phone to make sure it works. Do not make test calls to 911 (Service is not needed to make 911 calls). Most modern cell phones and cell networks can triangulate your position, this is very handy in an emergency.
16.) Lighter or water proof matches, or flint rod.
18.) 550 cord (named after its tensile strength) or para cord. Google the number of uses for this stuff, you'll be amazed.
I'll address some of these items in the next few steps.