A New Year, Time for Tickler Files - Breathing Space Blog
Create a file for days 1-31 of the month, and place it at the front of one of your file drawers. Behind that, have a file for each month of the year. If it's the second day of the month, for example, but you receive something that you won't need to deal with until the 15th, then put it in the file for, say, the 13th to allow yourself some slack. If anything comes in that you don't need to handle now, put it in your tickler file. This yields some immediate benefits. It keeps your desk clear and eliminates a lot of worry about where things go.
As the days and months go by, you continually take files that were in front and put them in the back. Once you get this system in place, you'll find that many of the things you file may not need to be acted on later. The benefits of this system are immediate.