Inspired by vintage beautiful design of Cathrineholm enamelware, I bought some enamel frost paint to give that vintage look to my plain drinkware.
Enamel frost paint, I found it in Michaels
Scotch blue tape
Make your template on a piece of paper.
cut 2 pieces blue tape, and trace your pattern on the tape.
Cut it with the Xacto knife
Tape your design on the glass and apply paint with a sponge is easier.
apply 2 or 3 coats and let it dry and bake for 30 min @ 275 in non-preheated oven.
The possibilities are endless, I used white frost enamel which is hard to see in the pictures. But there is other kinds of enamels such as gloss and 3D gloss and metallics. If you are looking for something brighter I recommend you use the enamel gloss.