Step 1: Getting some PVC to work with.
Step 2: Heat up the pipe
Step 3: Stencil out your mount design and cut it out
In the third picture, you can see a hole that was drilled for the camera. I made 4 of these, on 2 of them I drilled the hole after I was finished. The other two I drilled the hole before bending. Of the two methods I would probably lean towards waiting until the whole thing is formed and then drill the hole for the camera. If your forming doesn't work out exactly how you planned, your camera hole might be off.
While it is still flat, do all of your sanding. I used an 80 grit at first to remove all the ink that was printed on the outside and the wavy surface of the inside sands down as well. Next, I used a 220 grit to make it nice and smooth.