They are printed upside down so the front will be nice and smooth and easy to read. Use multiple colors like candy hearts. Even though these are not printed in NinjaFlex I'd like to let you know I sell small starter spools on my website 3dprintny.com for 9.99 , Amazon Prime (12.99) and eBay should you like to try out a flexible filament. Here is a good blog on food safety: https://blog.pinshape.com/3d-printing-food-safe/