Hi...I'm working on my first bed size quilt and am very confused about how tight to pull the backing when doing the sandwiching, as I've read conflicting instructions. I first pulled it "tight but not taut" as the book I was following said to do. Then I only used one package of 50 small curved basting safety pins as I never read in the book how many to use, ran out, so used straight pins--and boy was that a mistake. I kept pricking myself when I tried to machine quilt in the center and it looked horribly bunched up. I can't figure out how to center quilt with my typical machine-- with all this huge amount of material everywhere...is there some rule of thumb of rolling it somehow to fit around the machine better? I felt like giving up!
SO I undid absolutely everything, and I'm starting the backing from scractch again, this time intending to use around 300 pins as it's a fairly good size quilt--
My questions are this:

1)How tight do I really have to pull the backing material?
I will use t pins to secure it. It's going on the carpet as I have no table or area big enough otherwise.

2}How do I fit all that material under/around my machine to start sewing from the center?
There's hardly any room to the right...!

3}Does anybody recommend the "Kwik Klip" to help fasten the safety pins?

I have some arthritis in my thumbs and not wanting to make it worse and saw mention of this product on someone's website.

Thank you for any advice you can offer. I sure appreciate it!