Glass jars usually have metal lids, that can be spray painted. I do suggest to spray a clear coat to seal the paint. Those lids are much more attractive when they've been embellished with scrap fabric. The above lid is a baby food jar lid, spray painted in silver, then sealed with a matte clear coat.
To make these you need:
-jars with lids
-optional: spray paint to paint the lid, and clear coat spray
-metal compass with pencil
-thin cardboard, or used Christmas or gift card
-safe work surface
I cut a template using a Christmas card (back), and a metal compass with pencil. The compass is nice to use, especially if you have jars with different size lids.
Allow this to dry.
-add a thin strip of fabric to the edge of the lid, or for a background for a homemade label.
-you can decoupage fabric to plastic lids as well.