Ditching is not all that easy. Having the seams pressed properly and to one side makes that a much easier method. I like to gently spread the seam so I can see exactly where the needle is hitting. When I let go, the stitches are often hidden. On the other hand, I sometimes run high or low and when that happens, I accept it and move on.
FMQ is a matter of finding your personal mojo. The speed of the machine and the speed of you moving the sandwich have to be in synch. When you move too slowly, you'll have tiny stitches. When you move too fast, you'll have giant stitches. Moving evenly is important, particularly when going around curves.
Accept that your first piece is going to probably suck - it takes LOTS and LOTS of practice. I had to practice LOTS before I got good enough that I sucked. I was THAT BAD. lol Now I use matching thread to help disguise some of the less than perfect areas.