I use my large cutting table, not big enough for the whole quilt, but I have an "x" made of toothpicks taped in the middle of the table. I lay the sandwich out one layer at a time, centering each layer by feeling for the "X" with my fingers through the fabric. I use binder clips from the office supply store, or whatever I can find in a pinch (hairclips, etc) to hold the fabric taut at the edges of the table. When I've pinned an area, I move the entire sandwich and put the clips back on and pin a new area.