I have been "practicing" FMQ designs on paper for a while. By repeating the pattern with pencil (or pen) on paper you develop muscle memory. I recently did my first feather on a table runner and I was AMAZED how much my feather looked like the ones I have been drawing for a while. There are great designs out there. I agree that Leah Day has some great tutorials.
For me, the loops was my first pattern, followed by loops with hearts - or loops with leaves - or loops with stars, or......
Just start doodling on a drawing pad and see what you come up with. HAVE FUNNNNNN!!!