Staying organized is an on going struggle.
Since I like to buy sewing patterns during the 5 for a $1 sales and work up to them, I decided to make a library. When I'm at the store, I just pull out my smart phone and look through it to see what patterns I already have at home.
I took pictures of the front and back envelopes and created an album for them in Google Photos. Then I add a title to the info screen. This worked so well that I decided to include my fabric too. On the info screen, I add care instructions from the vendor. If I'm shopping for a project, this also comes in handy when I don't have the actual pattern. I just enter the search terms to view the images of the pattern.
There are also random project progress pics in the album; I named it Sew On & Sew On.
Here's some pictures: