My system works for me, but may be a little to "focused" for most.
All my finished jewelry is "mounted" on card stock with my contact information and a description of the piece, and placed in a clear zip lock bag. This serves a dual purpose - the bag keeps out the air preventing tranish, and is ready to display when I do a show.
I like to separate my jewelry by gemstone and store in plastic shoe boxes (bought dozens when they were on sale at Michaels at 3 for $1.00 several years ago.
The plastic boxes fit nicely in a small chest of drawers I found at a yard sale, with earrings, bracelets and necklaces each in their own drawers.
This may be a bit much for some, but works well for me. It is easy to inventory )Excel spread sheet) for replenishment and tax purposes and if someone wants to place an order, I know within a short time if I have it in stock or have to make.