It simply and safely and quickly helps to determine roof angles and areas for designing, or estimating or figuring the volume of a roof area on a house without actually having to get ON the roof.
Step 1: Print it out
I have use various thickness papers and double some up with double sided tape and then laminated it with scotch (type) tape.
Success is about the stiffness of the backing material and the hinges or pivot points. Grommets worked very well for me on thinner stock, but I could not find grommets that worked with thicker poster board.