Machine quilting requires an even-feed or walking foot to ensure quilting a straight stitch without distorting the layers, and a darning foot for free-motion or heavily curved stitching.
Use 100% cotton thread or size .004 nylon monofilament thread (clear for light-colored fabrics, smoky for dark fabrics) on the top and cotton in the bobbin. Pre-test stitch length and thread tension using two muslin pieces layered with batting. Adjust as needed.
Choose a quilting strategy. Begin stitching in the middle and work outward, making sure the layers are taut. Roll the edges of the quilt compactly to reveal the area being quilted; reroll as needed. To secure the thread, take 1 or 2 regular-length stitches forward, backward, and continue forward; stitch a few very small stitches and gradually increase to desired length. Trim thread tails.
Stitch "in the ditch" or along the seamline to secure quilt layers while adding subtle texture. Stitch open areas with a design of your choice.