This is a fairly new technique to me, and I have found that it has given me great results. It makes the quilting process less scary for me because I found the results to be predictable and consistent. I have considerably fewer puckers with this method than with the using just basting spray (my previous method of basting).
First, I tape the backing to the floor. I use Duct Tape or masking tape. The key is to get the backing fabric flat and taut, but not stretched. (Make sure you clean your floor before you do this.)
Then layer the batting on the top. My batting is extra large, so I line it up along 2 of the edges. This leaves me one big strip of batting leftover, and it is easier to see where to line up the quilt top.
Next, I lay the quilt top on the batting. Start at the center and smooth it flat working out to the edges.
Then, I used curved safety pins to hold all the layers together. Again, working from the center to the edges, smoothing any wrinkles as you work. You should pin every 4" or so.
After pinning is complete, remove the tape, (I also cut some of the excess batting off) and you are ready to quilt.
If you have any questions, please let me know.
If you have any other basting tips, or techniques that you use, I would love to hear them.