i did a project one time in which we taped a thumb tack - point up on the throat plate out the distance from the needle we wanted. Positioned the center of the fabric over the thumb tack and stitched away. Had to maintain conteol of the fabric but it worked fine. Might be able to put a thin ruler on top of the fabric to help hold it flat. At one time there was a vendor that sold one of the thin see thru 12" rulers with holes every 1/2". Such would work.