I kept adding borders to the quilt I am working on because I have a King size bed and a really high mattress and I wanted the top to come down over the dust ruffle on the bed. Now it is about 4" bigger than the width of my long arm frame.

Should I still center the quilt then when the main part of the quilt is finished re pin it to do one side then again to to the other

Or should I pin it off center then repin it to do the other side?

I have an 8" border going around 3 sides that I'm going to do in feathers, then a row of 3" flying geese to quilt that go around 3 sides of the quilt, then another 6" border where I'm gonna do ruler work like beadboard or something.

Any suggestions on how to approach this?

Can't help. Sorry to hear that. I will be watching this post to see what others suggests though.

It it longer than it is wide? Because you can put in on the short side unless its a square, then I don't know what you can do except maybe do what you can, as much as you can than reposition it.
Hope someone can help if I didn't.

The shortest side is too long. I'm definately going to have to do some repositioning. Just not sure how to approach it.

In order for it to roll equally on the frame, you might concider cutting the batting away on one side or both, and folding over the backing and top. Then piecing the batting back in and quilting the side borders at the top of the frame in 2 sections. I have done this and found it to work. When attaching the sides to the top of the frame, the weight of the finished quilt will hold tight and I only needed to attach the side borders to the top leaders and clamp the sides.

I might consider taking one of the borders off. It sounds like a difficult project and would make me hate quilting it. Just a suggestion.

I had this problem with a quilt and sewed my borders on afterwards using the flip method...BG and batting on back and then MF on front...stitch and flip over to form border and then quilt...worked quite well