Figure 13.
When writing "Happy Birthday" or something else on a cake, thin the icing with a few drops of water or extract to make it flow more smoothly. Write your message (in block or cursive writing) with a pen or pencil on a piece of paper. Tape the paper to a flat surface and cover it with a sheet of clear acetate or plastic. Practice going over the message several times. Keep wiping the icing away and trying again until you are confident. When making printed letters, hold the bag vertically. When making cursive letters, tilt the bag a little as you write.