Double-sided signs with arrows can be tricky. When setting up the artwork you have to consider what direction you want the arrows to point. When looking at the image on the computer it’s easy to assume that if you use the same image for both sides the arrow will point in the same direction. This happens because we are not thinking about it in a 3-dimensional view but as a flat view.
Most people provide one image with an arrow and request to print that image on both sides. When the double-sided signs are printed, we print the image on the first side, then we flip the board over and print the same image on the second side. Because the sign is flipped this will make the arrow point in opposite directions on the final sign. Not what you expected or wanted right?
Test it: Print the one image out on 2 pieces of paper, now put them back to back, you can see how the arrows point in opposite directions. This is the same for double-sided signs.
What you want to do is provide 2 images, one image for the front with the arrow pointing left and one image for the back with the arrow pointing right.