My dad tells a funny true story of an older guy in their church a while back who had Parkinson's and shook pretty bad and said you had to get out of the way when you saw him walking down the hall because you never knew which direction he was going.
Anyway, this man had befriended a teen in the youth group who would come over and help with house chores like raking leaves etc. in exchange for a donation for their summer mission trip.
So one day the two of them went out to a state park nearby to go fishing. The teen would have to bait the older guy's hook every time because of the shaking. Well the teen never even got a chance to get a line in the water because as soon as he'd bait the older guy's line, he'd catch something and the teen would have to re-bait the guy's hook.
Nobody else on the lake caught a thing and when they were leaving, a stranger who was watching came over and stated how he was the only guy on the lake who was catching anything and asking him for his secret.
The older gentleman with Parkinson's says "Well it helps when you're holding the rod if you move your arm back and forth like this"