I started my FMQ by following the designs in a preprinted panel, then took a class and started to practice on the grids and straight lines, progressing to stipple/ meandering.
One thing I can definitely recommend - that I learned from a FMQ teacher : Take your finger, and practice moving on the material the pattern you want to do. Do it as many times as you need to in order to get your brain to move the same way your hand/ finger is moving. Then go to your machine and go for it. She used a white board or pencil on paper to get the same effect.
The memory of doing the pattern with your finger will translate to your brain as you maneuver the material and your FMQ will go much smoother with less frustration. I've found it helps me figure out how to get into the pattern and get out of the pattern with a great deal less frustration.
Finally, practice on only one machine! I have three set up that I could use and I found I got really frustrated going from one to the other - just couldn't find that sweet spot! Sticking to one machine, I gained a great deal more confidence much sooner because I could measure my progress - I wasn't fighting the quirks of each machine.
I am nowhere near an expert, but since starting about a year ago, I am MUCH better than I was before.