How do you organize your paper?

I sort by manufacturer and then there's a handful of misc papers that are grouped together.

I recently did a major reorganization of my papers (except for cardstock, that's always been separate and organized by color). I went through my old collections and pulled out what I know I'll never use. Then everything else (including all of my SC paper) was organized by color. There were some that are too multi-colored to classify, so those I kept separate and organized by either design (stars/stripes/etc) or a theme (travel, seasonal, animal, etc) and put in front of the rest of the papers. I did keep some of the collections together if there were still enough to do so.

My only (ongoing for years) issue with this system is that I tend to keep the papers that are true 12x12 size separate from the 12x12s with a cut off strip. I'm afraid to mix the two because I worry I won't see the shorter papers (I keep things vertical) when I looking through them.

I still have separate cases that have very specific themes like holidays, travel collections, birthdays, school, etc. This is always a work in progress for me...

I organize by color.

Mostly by color or style for multi colored sheets ( stripes or dots )
There are a couple of things by theme Disney, Hersey, Halloween & Christmas type stuff.

I've always organized my patterned paper by collection/manufacturer. If there is matching cardstock I keep that with the collection too. All of my paper is stored vertically in my Kallax.

My card stock is organized by color with speciality paper in its own section. Patterned paper is by brand with collections kept together. Smaller amounts of brands are just kept together in a pile. Larger amounts of brands are either organized by date of release (Echo Park for example) or alphabetically (Basic Grey). I keep all my paper in vertical paper holders. Some vertical paper holder contain multiple brands. Other brands have multiple paper holders. For example, Echo Park has two, Shimelle has three, and Basic Grey has ten. I can just pull the vertical paper holder I want to use and then put it back on my shelf when I’m done.

by colour primarily - I only scrap 8.5x11 so I cut down to that size and store by colour (cardstock and PP - some colours are intermingled, others I have enough of to separate PP from cardstock).

you can see my paper storage in this picture - the folders on top are scraps - also by colour. The drawers on top - one has Christmas, one has Navy, one has military in general, one has Girl Scout - paper and embellishments - the other two aren't paper.

I do keep super themed paper in my theme folders (Halloween for instance) but I don't buy too much of that anymore.

Oh and within the Iris containers, the papers are mixed.

I sort first by weight, then size, and then colour/theme. Pads that are relatively intact are left alone, anything that's starting to lose its pages gets separated into expanding folders with the rest.
Scraps are in page protectors sorted by colour, in binders for solids, patterns and specialty (glitter/metallic/gilded/etc.)

I keep kits together and my other patterned paper is by manufacturer and grouped by collection. Once I’ve gone through most of a collection or kit the remaining papers go into the general paper population by color. My solid card stock is by color.

Paper is organized using the Cropper Hopper Paper Holders, Pouches, & Dividers. 

All paper (cardstock, patterned, & specialty) from my favorite manufacturers are stored together & divided by line. 

Patterned papers (not from my favorite manufacturers) are sorted by pattern (e.g. stripes, plaids, dots, woodgrain)

Specialty papers (not from my favorite manufacturers) are stored together. 

Cardstock (not from my favorite manufacturers) are arranged by color. 

I am having the hardest time sorting patterned paper! Say you have blue wood grain. (I do) is that in blue? Or wood grain? I have scads of paper that defies catagories, or so it seems! lol...

Agreed! It's going to work better if it matches up with how you think.

If you have two sheets you could split between the two categories if it's really not clear which one you're likely to look in. But in your wood grain example, if you were thinking about needing wood grain on a page would you search through that category and think "ugh, blue is not a wood grain color!" That's how I would react, so I would put that paper in the blue category. 

But some people don't think in categories and some people enjoy the serendipity of sorting through lots of papers to find what they want. It probably depends on how much you have and how well you know it.