I have fairly severe ME and the shakes nightly. I spend all of my time in a zero-G position except for sleeping. Sometimes I get jerking in the day but it gets much worse when I lay flat and attempt to sleep. It feels like some kind of storm passing over and through me with irresistible waves of trembling and shaking. You can’t fight it. It’s easier to roll with it. Breath work is very helpful. Sometimes I can redirect it with rhythmic movement - co-opt the shakes and entrain it into intentional movement. Once harnessed in this way breathe into it and let it dissipate. It passes, so you just have to ride it out.
As with pain management, fighting it just makes it worse. You have to embrace it and release it through acceptance.