start with a small practice piece to get the feel for moving your fabric around under the foot with consistancy. i don't change my stitch length but you may want to adjust yours depending on how your practice piece goes- if your stitches look too small- lengthen your stitch length, of your stitches are real big- shorten the length. practice good body mechanics, try to relax your shoulders---and breath.
in no time at all you will be quilting up a storm!