I usually pin baste but if it's a larger quilt (queen/king) I've gone to thread basting because it cuts down on the weight so much. I'm a hand quilter and all that extra weight is a pain to manipulate after a while. I use my cutting table to sandwich though. I center everything - regardless of quilt size - and use binder clips smoothing each layer as I go. When I finish the center section, I slide everything in whichever direction and repeat the process. It can get tedious on larger quilts but it beats crawling around on the floor!