I even use one hand to hold the center of the quilt down when I'm putting it in the frame- a bit lower than I actually want it, because, as you know, it snugs up when you snap the outer pieces on. Then I use my other hand to arrange the quilt over the frame and snap the pieces on. As others said, if you turn the covers on the pipes toward the center, that will loosen it up a bit.
I'm also one of those that quilted my first quilt without a frame/hoop. I tried it again the other day and it feels awkward to me now but it worked for me then!
And for the record, the fact that there even IS a quilter's knot is recent news to me!
Don't give up, just keep practicing and it will soon not only become easier, but you may actually find that you enjoy it! ;-) Hand quilting is such a satisfying, relaxing activity, once you get the hang of it- truly! :)