I am making a cake for a dinner we are having for our Awanas program. I am going to use the color fill technique with royal icing to make the logos for the different clubs and want to put them around the cake. Once they are dry and I am ready to attach them how do I do that?? Do I use royal icing or water or how? Thanks for help.

I have never done this before so I may be talking out of my back pocket but I would assume that water would melt the color flow. If I were doing it I would probably use royal icing.

If I understand your ? right you will make decos using the colorflow technique. If so just pipe an open circle of b'cream on the back and push it against the cake gently but firmly.

Oh wait, you didn't say how the cake is iced....is it in b'cream or fondant?
If it is fondant, then use royal icing to pipe that open circle. If it's b'cream then it can be done with either b'cream or royal.
If the decos are rather large (like 4"x4") then several circles on each would be best.

OR: you can pipe spikes of royal icing on the back of each piece. Just turn it over, pipe tip 3 or 4 pull-up straight lines about 1/4 to 1/2 inch long. How many depends on how large the deco is. One if not much bigger than a pingpong ball. 3 or more if larger. Let those spikes dry well and push those in the cake.

**Do NOT use water**.

Thank you The cake will most likely be iced in fondant. My buttercream is not smooth enough that i feel comfortable covering a whole cake in it.