Measure for the handle.
Decide how tall you want the handle. I love the drama of a tall handle, so I make mine between 15" and 18" tall. (You can definitely make it shorter if you prefer.)
Tear off a piece of parchment paper that is about 8" longer than the desired handle height. Once the cake layers are cooled measure the diameter of the layers. You will make the width of the handle 1" less than the diameter of the cake.
Using a ruler, mark the center of the parchment paper. Then make parallel markings to each side of the center line the width of the handle. For instance, if the cake layers are exactly 8" in diameter, you will want the handle to be 7" wide. So after marking the center line, measure 3 1/2" to each side and make those marks the length of the paper. This will be the line your wire follows.
Then measure the HEIGHT of each layer and add those together. If each layer is 2" high, then you want to add 4 inches to each side of the handle to stick into the cake.
For a 16" high handle, you will want about 40" of wire. Since wire comes on a roll, you will have to do some straightening and manipulating of the wire to get it to cooperate.
Tape the wire to the parchment paper...not much sticks to parchment paper, so it may take some doing. This is just to stabilize the wire while you are piping the icing.
Make the Royal Icing and tint it using the Yellow Gel Icing Color.
Prepare an Icing Bag with a coupler and the Star Decorating Tip.
Fill the bag with the yellow royal icing and pipe "S" shapes onto the wire, making sure they touch one another.
Let the handle sit at room temperature until fully dry. This will take at least 24 hours. Make sure it is completely dry before turning over or it may crack.
When totally dry, CAREFULLY lift the handle up and turn it over, at this point you can remove the tape. (The handle at this stage is very fragile.) It's okay if you can't remove all of the tape, it will be covered by the icing.
Then pipe icing onto the back side of the handle.
Let this dry for 48 hours. There will be no more shine once fully dry.