I'm no expert, but have FMQ both on my cheapie Brother from Wallyworld and my fancy Elna. Besides dropping the feeddogs, and using a darning foot, the only thing I do with tension is loosen the top stitch (thread) just a tad so it doesn't pull on the curves. several of the comments already given are important--new needle, clean machine (a tiny ball of lint can cause problems with the bobbin), and ALWAYS bring the bobbin thread up to the top of the fabric before you start the FMQ! Other than that practice,practice, practice! And drawing out your designs on whiteboard or paper really does help get that muscle memory. Check out some of the tutorials on the web for some ideas beyond stippling, too.