I just FMQed my first quilt - a large lap quilt. I found it hard to maneuver it around at first but it got easier with experience. I took Leah Day's advice and gave myself permission to mess up. I think I had a pretty credible result using Golden Threads paper with the stipple design needle-punched through it. I pinned the pieces to the quilt and FMQed over them. (I hated this but I was afraid of marking the white areas.)
After it was completed, my DS commented on the quilt and I said, "But look I did make some mistakes." He asked me to point them out and guess what, I had a hard time finding them.
Good luck, give it a try and don't be hard on yourself.