When my fingers hurt after too much time on the keyboard, I when my finger hurts after typing too much i would give my fingers a breake.But if youhave to keep going you can just roll you hands around and keep going .

What really helped me improve my typing speed is doing typing games and learing my where all the key are at on the cumputer.Also sitting up so when i sit up it is esay for me to know where to put my fingers and type.