One of the practices is with paper and paper ... open up that tablet and relax and start doodling.
Since I too have control issues, I practice while I work, and my first quilt was SOOOO stiff, too small stippling is NOT a good thing ...
It wasn't until I was wanting a new pattern for quilting, since one pattern over and over is boring, that I considered the paper and pencil. Use a pencil because it will create a drag, and gives you more control <g> ... feels more like what you are going to be doing with your machine.
I hate practicing for no good reason, so I would encourage you to declare your practice pieces for charity.
Our LQS teaches long arm classes. Using their fabric, batting, machine and backing, we learn/practice. When they have enough quilting on a piece, they bind the whole thing and give it to an animal/pet shelter ...
the fifteen inch squares recommended are grand ... you can practice joining them together to make a nice little blanket for some lonely animal ... or ... make them twelve inches, bind and use as potholders.
There is no rule that says your practice pieces cannot be turned into perfectly practical items ...
and practicing your name or words of encouragement or the year ... the idea is to get familiar with what you do that makes the machine do something ...
I put feed dogs down, since they don't do anything under free motion quilting, anyway, and all they are doing (in my humble opinion) is scratching up the fabric used as backing ...
Finally ... after you have put your feed dogs down
put on the darning/free motion/embroidery foot
threaded your needle
loaded in your quilt
PUT THE FOOT DOWN ...
something I have learned from this site ... if the back/front has long stitches, you are moving the fabric too fast ... even a stitch regulator can be over ridden if you go fast enough ... after all, it is only a machine, not a mind reader ....