Road Sign visibile from both sides


Is there any way creating a road sign that the texture stays in proportions when added to the object not from a plane? ( the plane is visible only from one side and I would like to see the sign that are on pillars from behind. I would also like to color each sign in a different color - by pairing two planes it will be in different colors and I would like to see the same color from the back and front).

You could make the planes have the same color if you did 2 planes back-to-back. The difference in color would then be the lighting.

You should look into making a sign in a 3D modelling program, that way you can paint/texture them however you like and make them double sided!