To make the outlines on your stained glass jars, you will need to use black or gold glass paint outliner or simulated liquid leading. These can be purchased from craft stores or from online retail stores.
You can also make a homemade version using acrylic paint and white glue. Simply mix two parts white glue with one part acrylic paint in a squeeze bottle (a small nozzle works best). Mix thoroughly by stirring with a stick or small spoon.
To color your jar, you will need different colors of transparent glass paint or glass stain paint.
You can also try making homemade glass paint using white glue, food coloring and liquid dishwash soap. This homemade version is water-based, therefore the paint will not be as permanent as the commercial ones.
Use your stained glass jar as a flower vase. Place real blooms or craft your own paper flowers. You can print out these flower sets or these flower shapes sets. Color and cut out the flowers, then glue a pipe cleaner or drinking straw at the back of each flower to make a stem.
You can also try making these easy paper flower crafts: