You’ve been given very good advice here Sarah. Like Teri beginning of the week, or even a couple of weeks ahead, make my icing and fondant. I cover the cake board and make any flowers or any other embellishments.
I bake my cakes ahead of time and freeze them. Makes them moist. Take them out 2 days before, thaw. That would be Thursday. I crumb coat, cover in icing, put in my dowels and cover in fondant. Rest overnight.
Friday I decorate. Take pictures.
As far as the royal icing piping, I’d make a couple of batches, different recipes, see which ones you like. I practice piping on a overturned bowl. As far as piping on the cake, I would attach your flowers first with melted white chocolate. Then pipe the lines to join. You could actually practice that on a fondant covered dummy.
Take your time and enjoy this. You will be fine.
Creativity is God's gift to us. Using our creativity is our gift back to God. Clarky's Cakes 😎