This was a topic about a year or so ago and someone suggested pinning on a wall....sounds crazy, but listen. I have a back issue so I can't pin on the floor anymore. I tried this and it works and is soooo much easier and quicker.
I placed a large tablecloth (vinyl) on the garage wall, using velcro. Next, using blue tape, or masking tape, tape the backing (face down) onto the tablecloth. Spray baste with an adhesive, and add the batting. I pin about 3 or 4 pins at the very top to help hold. Next take your top (well starched) pin on the top so you can lift up then spray with the adhesive (seems to work better on the top vs the batting). Smooth out slowly, making sure all the wrinkles are removed, then pin to your hearts content. Finally, remove the tape and start sewing.
I've done up to a single bed size using this method and will be trying a queen this summer (if I ever get done with the top :)).
Hope this helps.