It was a long time before I could "scribble"! When I started off, my loops and swirls look much better than my stippling, so I did alot of those until I felt comfortable enough to move on. Practice is the key. There are Skillbuilder panels that you can sandwich and do.
http://about-quilts.com/store/fabric...practice-panel
You could even make up your own by drawing some of your favorite designs on muslin. Then sandwich and practicing following the lines. I recommend using a different color thread each time, then you can see how much you have improved as you go along.