I pin my sandwich with regular long safety pins, about 3-4" apart. I have a small glass topped dining table so no need to worry about scratching the table top. For a long quilt I set up a 4x8' folding table at the end and just pin and smooth until it is all pinned. I use clamps from Home Depot to hold the sandwich to the table. I have done many quilts like this. Everyone has to try to find what works best for them.