Ask for help
I think my biggest tip for organizing paperwork is to ask for help. Personally, I'm a "piles" gal. Central station for all paperwork in our house is my desk. Everything goes into piles.
But then my desk gets cluttered. So eventually, when it gets too overwhelming, I ask for help. It can be a friend, a partner, a parent. But you have to ask.
We sit on the floor and go through the piles. We use my system, because otherwise I'll never find anything again. That doesn't necessarily mean I don't have to send periodic emails to my partner (who helps me stay organized) that says, "If I were X, where would I be?" But that happens with a lot of things in this house because my partner likes to rearrange things on a frequent basis!!
I have two file cabinets at my desk and 8 downstairs in the basement. I keep a box of manila folders at my desk. When I go through the piles, everything gets a home ... even if it's the recycling container! I keep a recycling container at my desk as well, so that when I go through the paperwork, I can toss anything I don't need to keep right in the recycling.
Upstairs I keep files related to my work, school for my child and current court papers (for a custody suit I'm involved in). The rest lives down in the basement.
My son dumps old tests and schoolwork on my desk. They go into a file labeled "schoolwork." I keep all of it in that file until the end of the school year, in case he needs to go back to something he's given me. At the end of the school year, that folder gets cleaned out and recycled and waits for the next school year to begin.
I also keep a folder labeled School Info. All of the beginning of the year paperwork goes in there, and anything else that comes home during the year. Again, that gets cleaned out at the end of the year and the file sits empty until the next school year.
I keep a Report Cards file and Test Scores file as well. They don't get cleaned out.
Bills go downstairs, although we have gone paperless to a huge extent, which really helps. But any announcements or updates to terms all go in their properly labeled files in the basement.
The basement is also where I keep instructions. Personally, I would have separate files for instructions - like appliances, toys, computers, etc. But my partner simply dumps them all into one file. I just haven't gotten around to organizing it. :) Guess I need help on that one! ;)