Take a look at this nifty tool. I used something like this for many years to press out royal icing in-between walls, and after changing the tip, to create all sorts of designs and squiggles for each gingerbread house. Last year, my well-worn dessert press just gave up and broke all of a sudden. The thumb piece snapped off. I've found a new press, pictured here, and I know it will last. Use it to save your hands while you are squeezing thick royal icing for hours on end and you will be amazed at how fast and easy you will fly through this phase of your project.