I guess it depends on what you want to do with it. I would not really use it to cover a large area as it can be expensive and doesn't provide much traction. If you did want to use it to cover your floor, I would get some 4X8 sheets (as many as you need) and duct tape them together. If you are using a pen, then you don't really need to make edges. One problem this could create is that it will be hard to move and store if you need to move it.
I only use coroplast in the cages. I cut it so that the bottom is a bit smaller than the cage dimensions (1-2 inches). If you have a big enough piece, then add 4-6 inches on all sides for the edges. I then cut out the corner and tape the edges together. You may need to score (cut 1/2 way though) so it bends easier. I also use poster hangers over the edge to prevent chewing.
I do have a pen that I use. I have a small tarp that is 4X6ft. I put interlocking mats over top and the pen doesn't go all the way to the end. This is easy to clean and easy to put away as I can't leave it up all the time. A tarp is a good idea under them as pee can get between the edges, so the tarp would just protect the floor. The mats do provide traction and are easy to clean.