Roll out your fondant on a clean surface. Once you get a nice size of the rolled fondant use your round cookie cutter and cut out as many round pieces you can.
Felt - this piece will be your stamping pad that you will put the gel food coloring on. You will need 2 pieces of felt - 1 for the red and 1 for the blue. Make sure you have enough gel on the pad to cover the image of your rubber stamp. Be careful to only get the gel on the image not on the negative space. It can make the cookie have a "ugly" spot.
Using your blue food coloring gel pad pick up some ink on your rubber stamp and press the image to the prepared round pieces of fondant. Do all your pieces of fondant because you are going to clean your stamp with soap and water to get it clean for the next color.