I always add meringue powder to my bc icing Hannah. Helps it crust, set and stay firm. I don’t know where your from, but here in Southern Ontario, Canada….it gets very humid & hot. So in some cases, I do a 50/50 icing of bc and royal. The royal really helps keep the lines you create sharp and crisp as well. And as Clare stated above…tylo powder will work too. You know Hannah, I purchase a wide spaced hair comb at my Dollar store, and used it to create lines in my cake. Keep it just for decorating. Amazing the ordinary things you can find in your hardware or dollar store to use as “tools”…. And there cheap too.
Creativity is God's gift to us. Using our creativity is our gift back to God. Clarky's Cakes 😎