Typing with shaky hands, any way to help?

There are two options in System Preferences>Keyboard that should help:

Try turning the first toward "Slow" and the second torward "Long" and adjust to the best setting for you.

Cheers and best of luck,

GB

Hello

You might enable and adjust the "Slow Keys" function via accessibility section in System Preferences. The below is a screenshot under OS X 10.6.8. Later versions may vary.

Good luck,

H

Here's how System Preferences > Accessibility looks in 10.11.2 (El Cap):

SG