good old conscious competence. It's in your mind fool!
You are over thinking the task and the stress from concentration amplifies your shaking (kind of like performance anxiety).
just do it real slow over a sheet of white a4 paper so you dont give a shit if you drop all of it at one stage and go into a fit of rage like I used to when time was pressing and I needed to get going. One day I sat down and rolled 1/2oz into joints for a mates 40th birthday and that pretty much solidified the skill.
When you do it a few times slowly and make a few smokeable joints (who gives a toss what it looks like? as long as it burns evenly I think) you will move into unconscious incompetence and live happily ever after.
rip open a cigarette and keep rolling it up and unraveling and starting again. Good luck!