I live in a desert climate, the air is very dry and my icing crusts quickly. I am limited on wet on wet because of this. I outline and flood with the same consistency. I make my royal and keep the bowl covered with a moistened kitchen cloth. I use a liquid measuring glass to mix my color and transfer the whole amount to a piping bag. Then clean my measuring glass and mix my next color. The amount of color bags depends on the project - but they are all flood consistency. I work with one color first, outline one cookie, then immediately flood it. After all the cookies are done with the first color, I start the second color. After I am done flooding, I do one of two things with the remaining amount in the bags. One: empty bag into a cup and add confectioners sugar to thicken, transfer to parchment triangle to add details to the cookies. Two: empty bag into small storage container with lid and put into freezer. If I need a detail color not already mixed from flood consistency, I will mix the color in a small container as I need. I always check my freezer for colors I used on past projects (may need to add color to darken, add white icing to lighten or change the consistency). My freezer has about 20 small containers of various leftover colors at any given time.