I thought once, I sprung for the combo setup, I would become a pro too, but that's as far from the truth as it gets. It takes tons of practice. I got mine with JoAnn's had their black Friday flannels at .90 a yard so I made twin quilts for all my nieces and newphews (about 20) and used them for my practice. Get yourself something that you won't feel bad practicing on and play, that's about the only way you can get comfortable with things. Still today, I would rather use my domestic machine for a lot of things. If I am going to use a pantograph, the long arm is great. But I don't care for using my machine from the front for free hand, and that's just a practice thing for me too. I've had my machine for about 8 years now!
If you have a quilting group in your area that makes charity quilts, frequently they are looking for someone to long arm their quilts. It's all for free, but a terrific way to get practice without building your own quilts. From my experience they are just delighted to get them quilted and are not looking for perfection.
Hang in there, things will improve for you!