Here are some tips on organizing paper files:
* On the file folder label, put the date first, where appropriate, and then the subject. I use the yyyy-mm-dd format, where yyyy is the four-digit calendar year; mm is the two-digit representation for the month, with leading zero for January thru September; and dd is the two-digit date, with leading zero.
* You can then organize the folders in chronological order or reverse chronological order. Arrange the files vertically. I love the brightly patterned hanging files from the recent collection that Mexican designer Sami Hayek (he's also Salma Hayek's brother) did for Target.
* I occasionally use color folders, but not for color-coding. Inserting a few color folders among plain manila folders helps break up the visual monotony.