This is how I practice my FMQ. Maybe it will work for you. I've made up a bunch of candlemats, and just FMQ on them. If they turn out badly, no big deal. I also took a class with Christopher Nejman one time, (he is not a quilter, but is a great teacher). Instead of taking a death grip <grin> on the fabric, take the 2 botom corners in your index finger and thumb and just gently guide. Since you aren't using a large piece, it makes it so much easier to practice on. As you gain more confidence, start moving up in size.
BTW, there has been several times I have forgotten to lower my feed dogs and it still turns out great. I'm to the point now, I'm keeping my stitches consistant. I hope this helps you out. It works for me.