I used 1/4 inch cork and made a trio of SUPER coasters for my super friend, Mike.
Each coaster measures 4 inches by 3 1/2 inches.
I made a custom stencil for the shield (you can read how to do that here).
I used a sponge brush to dab the paint onto the coasters.
Each coaster got several coats of clear acrylic seal, for water repelling.