What do you think is the best way to write instructions for those that are not trained in emergency techniques?

I'm going to include in my bug out bag (b.o.b.) instructions for how to use the items in the b.o.b. for my loved ones and friends (or worst case, anyone that finds my b.o.b. and needs to use it). Most of the items in my b.o.b. are multipurpose i.e. bandana... or their uses are not very obvious i.e. vasoline soaked cottonballs... or they must be used with other items i.e. emergency blanket + black cup = solar cooker/ solar water-still. This is why I want to include these instructions.

My questions are these:
I have to consider the reading abilities of whomever uses the b.o.b. What level of reading skill do you think the instructions should be written for? 5th grade, maybe?

Should it be written in an informal personal style i.e. You should stay hydrated. This style seems like the author is speaking directly to the reader.
Or
Should it be written in a formal instructional style i.e. Stay hydrated. This style seems like stereo instructions speaking AT the reader.

Which style do you think would be most effective. Both styles can relay a message to the reader so s/he can survive the emergency. One might keep the reader at ease and the other uses less space, which equals less weight. But, does that weight savings justify sacrificing possibly keeping the reader at ease?

With the above considerations in mind do you think numbers should be written out i.e. three feet of duct tape ... or shown as characters i.e. 3 feet of duct tape?
I know there is a grammerical rule that states that all numbers below 11 should be written out and all numbers above ten should be shown with characters, but that rule didn't take the considerations above into account.

Here is a major consideration that I've been toying with. Should instructions for each item be attached to the item?

Well, that's all for right now. I'll write more later. I look forward to reading your replies.

Thanks
Wayneburg