To write “Happy Birthday” or to make a simple decoration on a cake, it is necessary to have either a small pastry bag fitted with a small decorating tube, or a decorating cone. It is extremely difficult to explain in words how to make a cone from a triangular-shaped piece of paper, but it should be easy for you to follow the drawings.
Start with a square piece of parchment or waxed paper and fold it in half to form two triangles, cutting to separate them.
The triangle in front of you should have a point facing up. Bring one of the corners up to the top of the point, twisting it gently so that the two points meet, forming a cone. Holding the two points together with one hand, wrap the second corner up and around the cone so that it joins the other two points from behind. If the point of the cone is not tightly closed, adjust the ends to close it. Use a stapler to fasten the three points together or fold over to secure them. Fill the cone half to three-quarters full with royal icing and fold the top of the cone over several times to securely enclose it. Again, use a stapler to fasten the folds shut.