I use my cutting table regardless of quilt size. I lay out the backing and use the big binder clips to hold that in place. Repeat with batting, clamping that into place with the binder clips and follow the same process for the top. Pin or thread baste that section. If the quilt is larger than the table top (which it usually is), I unclip everything and shift the whole shebang to where a bit of the pinned section will still be on the table top. Clip that into place and then start working on the remaining sections with the same process.
It can certainly get tedious with all the moving around the table and such but I'm not bending over or crawling around on the floor.