The whole buying a ton of patterns has led to a problem - forgetting what I already have and repurchasing the same patterns more than once. About a year ago I decided it was time to get organized so that I could easily see what I have. That way I could spend my dollars on new patterns and not repeats. After much thought I came up with a system that works great for me and I am hoping will inspire someone else who is addicted to patterns as well.
The major pattern companies all have their pattern books. You can go into the store and look at those glossy books and imagine the possibilities! Then if you find a great one that you just can't live without you find the pattern number and go find the corresponding pattern in the drawer of patterns. Well, that is where I found my inspiration. My own mini pattern book and pattern drawers.
I began by photocopying the front and back of the envelope for each of the patterns I own. You can take the envelope apart and lay it flat and only have to copy it once. The other option is to go to the website of the pattern maker, find your pattern and then print the same information from there. I have done both. Once I did this I started sorting my patterns into categories. I then triple hole punched each of those copies I had made and put them in a binder under the correct category. Within each category I group the digital patterns and the commercial patterns. I then put the commercial patterns in order by the number the pattern company assigned to them (just to make it easier to check if I have a pattern). I don't group my commercial patterns by company, just by the number. For my digital patterns I group them by designer to make it easier to check if I have already purchased a pattern. 
Now here is where it gets really fun. I took each pattern and put it in a manila file folder. I then numbered each folder and then wrote the same number on my copy of the envelope in the binder. The actual patterns in their file folder were then filed in numerical order in a filing cabinet or two. Every time I get a new pattern I number it one higher than the last pattern in my drawer, make copies of the envelope and put the same number on that copy, file the numbered pattern in the file drawer and the copy in my binder under the right section.
I now am able to grab my pattern binder and look through what I have. If I want to make myself a skirt I go to the women's section. If I am looking to make something for my kiddos I open it to the kids section. I can take this binder with me to the store and check if I have a pattern so I do not repurchase one I already have. Since I copied both sides of the envelope I can also take the binder with me and have the supply list of what I need to make any pattern that I own.
This has been a spectacular system for me and I hope some other pattern addict out there also finds it helpful. Stay tuned for next week when I will share how I print and store all those cute digital patterns I find online. I use the same system above for cataloging them, but I have a special system for how they get printed and stored in the file folders.
