First, wash, dry, and iron napkins to ensure they are clean and wrinkle-free.
Next, pour a small amount of the fabric paint on the lid or palette.
Use the roller brush to roll paint on the stamp. Test out your stamp on a piece of scrap fabric.
Once you are happy with the test version, unfold your napkin and stamp it. Then set it aside to dry.
To heat-set the fabric, use an iron on the highest setting for that fabric and turn off the steam. Iron for 3-4 minutes, using a press cloth to protect the ironing board.