Hi Angel, welcome to the board!
I roll the quilt in from each side, using large clips to hold the quilt from unrolling (look on the internet for them i bought mine years ago, but they are still available). Leave a 10 to 12 inch section in the center of the quilt to work on. Start quilting in the very center, work to the top, and then go back to the center and work to the bottom. Roll out one side to give you another 12" to work on, taking up the area finished with the other roll. Continue quilting this way until one side is finished, re-roll and go back to center and start working to the other edge.
By starting in the very center of the quilt there is less chance of catching a bump in the back. You are always smoothing the fabric and checking. If you have a very large quilt, you can rest the rolled edge you are not quilting on top of your shoulders. Helps to carry the weight of the quilt from not pulling the fabric on the machine.
Hope this makes sense, I've machine quilted this way for 30 years
Here is a small visual of how I roll and the center area for quilting. Try it on a small wallhanging or table runner to get the hang of it.
Good luck
Pat
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