How do you organize your backpack?

[Purplecat]

Second page:
Official Valve items from official class updates goes here, and sorted per class.
First column on the second page is for community and event items that are my favorites. If it's here, I'm probably using it time from time (with the exception of the KGB and FAN).
My favorite hats and items are stored here too.

First page:
The two bottom rows are the scrap idea, where I keep extra weapons for trading/crafting/metalmaking.
Unique items that I don't care too much about is on the left side of the (refined) metals.
Extra yet rare items (mostly hats) is on the right of the (refined) metals.

Remarks:
I have two gibuses. Valve need to make it a valid hat for crafting, I don't have the heart to delete the extra one outright. :/
I used to have WAY more metal, crafted it all in the hopes of getting a golden wrench. :3 (Well, and that it was getting annoying having so little space).
Team Fortress 2 have a preference over equipping the newest item in your backpack, rather than your oldest (or the one with the highest level), needless to say... this gets quickly annoying if you're trying to organize it like me.
Engineer is the only class I have no hats for.
I only used the "craft class hat" and "Rebuild headgear" recipes one time each.
Someone(/several) accused me of using a command to fake the hatcrafting when I pretty much crafted 8 hats at once, that was funny...
You can really tell I used to idle...

So enough geeking out for me. Now I'm curious how you guys do it. :3

[Ignis Solus]

I use the automatic sorter, "sort by type".

[Purplecat]

I used the automatic sorting at first, but it... gets annoying way too quickly sorting out your duplicates from the uniques.

I'm hoping for Valve adding a third page so I can make my first page fully "scrap" again, but it's probably going to be awhile until they do that (sometime after the large polycount update?)

[Mr. Munchlax]

My inventory has always been extremely skimpy due to me not being able to play during most of the time the backpack system was out before crafting and all that stuff... so I've never even had to use the second page, I just use the sort by class to quickly find class items to smelt together... It took me 6 months to get enough crap to craft a pyro hat... I got the brain slug, which I use but I really wanted the fireman hat or the rubber glove... and to much distraught, I was dropped ANOTHER brain slug the night the engie update dropped... *sigh*

[Arcalane]

I sort by slot and toss dupes/stuff-to-be-crafted into the bottom right, other stuff into the bottom left.

[skunkfox]

uhhh why don't any of you use the sort by equiped selection? It'll load the first page only with what's equiped and leave all the duplicates to the bottom of the first page, and so on. (I lost my level 100 items due to TF2 glitching! Nuuuuuuu poor level 100 sandvich ish lost forever!)

[Gami]

i recently put all my hats on the second page of my backpack, since i regulairy craft stuff i use the first page for it, and it never gets full so :B

[SilverWolf]

First Page:
In the first page I keep my metal, dupes and other items, to me it doesn't really matter where I place them

Second Page:
In the second page I order things as following:
Each row represents a class, each column representing a slot of up to 5 columns (a craft page basically).
Main weapons sit on the first column, Secondary weapons on the second column and so on, 4th and 5th columns are for extra unlockables (such as community made items).
Rows are ordered by class number (1 Scout, 2 Soldier, 3 Pyro, etc.)

[STrRedWolf]

[Jinx]

Jinx's backpack

I do mine similar to Silver and STrRedWolf's but my second page is starting to feel too cluttered with all of the community items they're coming out with. I might move all of the hats and misc slot items to the 2nd half of the first page and just use the 1st half of the first page for crafting purposes.