I mentioned in my last post that I originally had my scraps sorted by color. I had them in gallon baggies by color family: reds, blues, greens, etc. When I started working seriously with my scraps last year I quickly discovered that, for the way I was working at least, having them sorted by general size would be more useful. That's when I dumped the bags into a laundry basket and started sorting them by size as I worked. The smallest pieces stayed in the basket and the long strips went into something else. Eventually the strips were transferred to the plastic box you see on the right in the picture below:
One of the other things I've done is to make the decision to cut a few specific size patches from the leftover fabrics that are too small to put back in my stash but too big to qualify as a scrap in my book. I have two tins from the thrift shop. One hold 3.5" squares and a baggie of half-square triangles that go with them. The other holds squares and triangles and a few rectangles in the 2.5" dimension. From these I can make simple 6" blocks and 9" blocks like Shoo Fly or Churn Dash or 9 Patches.

This system developed as I was making the blocks that ended up in my "Souvenirs" quilt that I shared in my first post. That quilt is made entirely of 6" blocks. I've since been able to put together a couple of other quilts in relatively short order because I had patches already cut and could make up blocks quickly.
Another component of my scrap system is a glass relish tray that I keep on my sewing table. This allows me to sort scraps by size as I create them while I'm working on a major project. I can either use them as leaders and enders (a la Bonnie Hunter) or dump them into the appropriate container when it starts to overflow.
This system developed as I was making the blocks that ended up in my "Souvenirs" quilt that I shared in my first post. That quilt is made entirely of 6" blocks. I've since been able to put together a couple of other quilts in relatively short order because I had patches already cut and could make up blocks quickly.
I am fortunate to have a room dedicated as my quilt studio so I can leave things out overnight no matter how messy it looks. (Not always a good thing!) Everyone has to find what works for them and their circumstances. It takes time and it takes tweaking.