Here's a quick and easy way to display your jewelry at home (you would want something a little heavier and less crowded for selling display.)
you need a foam core poster board,
fabric big enough to cover the front, plus two - three inches extra on each side.
painters tape (It lets you remove the fabric and re use it, when you are tired of it for the display)
Place the fabric flat on a smooth surface (I used the floor). Put foam core poster on top of it. Use the painters tape to tape the extra fabric to the back. Take your time and make sure it is smooth in the front.
Now use three or four thumb tacks to hang the covered board on the wall. Put jewelry up using the thumbtacks as well. use the jump ring or ring toggle to hang by. If the fastener is magnetic - just put the tack in and then let the magnet attach to it.
I mostly forget what I do and don't have in my jewelry box if I can't see it and this is a good way to keep things in sight, without getting all tangled up.
If you want something a bit thicker, go to the home improvement store and get strofoam insulation board - it's great stuff and works well for this also. If you want - you can also order the pins that are shaped like a "U" that are made for pinning jewelry to a display board.
What I like most about this way of storing jewelry - it's like having a constantly changing piece of art on the wall.