I found a great way to do straight line quilting. In the book One Line at a Time: 24 Geometric Machine-Quilting Designs Made Easy by Charlotte Warr Andersen, she uses removable paper paper backed labels as guides to quilt by. No marking the quilt top and the labels comer right off and are reusable. She uses the 8 1/2 by 11 labels. I had to order them online. In her book she has straight line patterns you can trace and print on the labels. The labels really makes it easy.