Originally Posted by DanTwoLakes
One way to weight down the plastic is to sew pockets on the bottom of the plastic and slip in metal electrical conduit. You can easily sew the pockets in with a home sewing machine and a helper. This can also be done at the other end so you can screw the conduit to the ceiling with conduit clips. Use the clips with one end open so you only need one screw per clip.
I just wrapped mine on 2x4's at the floor and stapled it in place - which takes care of the billowing Dewey mentioned. I used 4 or 5 rolls total of 10x20x.003 clear plastic, stapled to furring strips then screwed to the wall studs under the 'rock.
But --- whatever works for you to keep the dust off of the surface is the best way, regardless of how you choose to do build your "booth".