I push two banquet tables together and layer backing, batting and top making sure everything is centered. I use the big binding clips all around
starting in the middle of each side. North/South then East/West. Then add more all round making sure it's taught but not overstretched. After I'm done
basting the middle, I move the basted centre to one corner, put the clips back (again making sure everything is taught) and baste, etc. One more
thing that helps is to starch your backing. Don't hesitate to use those clips.
I think I put one about every 8-10 inches.