I like to break down everything into categories starting with the most important.
1. Water
2. Food
3. Shelter
4. Hygiene
5. Medical
6. Defense
7. Information
8. Entertainment
From there I add sub categories i.e. "A. Canteen" under the category of water. I also further divide subcategories such as listing a sharpener under the subcategory of "knife". That lets me keep up with what I have and helps point out all the little items that are easy to over look like a knife sharpener, cleaning kit for a rifle, and nail clippers for hygiene.
Think very hard about the items you list and all that goes with each item. You might list socks but socks alone aren't enough. You want clean dry socks to prevent hypothermia, trench foot, and/or some foot fungus. Now how are you going to ensure you have clean dry socks?
The danger in listing items this way is that it's easy to make a list of stuff so large that you couldn't possibly carry it all, or couldn't carry it far. Keep weight at an absolute minimum.
Just my .02