I thought the software was just to print the decals, I use GIMP to design and do my concept work, I love it. It's a free version of photoshop, and if you aren't sure the best way to do something, there are youtube tutorials, so it makes it easy to self teach. The images below were done on GIMP. The nice thing is that I was able to specify the dimensions of the artwork after i created them, so I'll try to do a test print to see how accurate it is.