I don't mess with the tension or stitch length at all...just use your darning foot (make sure its down). You speed with which you move the fabric and your movement will determine your stitch length. Try to move smoothly..it doesn't really matter at this point whether your stitches are big or little...just try to move smoothly so that they are consistant.
I had that stuff on the back when I forgot to lower my foot on my machine. You'll get it...hang in there!!!! Oh...and be sure to hold your mouth right :wink: