What really helped me improve my typing speed is...is using white out on the keyboard and then just typing on some tests or just having conversations on Facebook, or Messenger. This was the only thing that works for me, try it sometime if you are having trouble remembering the keys...

When my fingers hurt after too much time on the keyboard, I ... usually run them under some cold water for about five or six minutes, to numb them a bit. Than i add some novocaine to soothe the burn that comes after the numb wears off. Than it's back to the old key stroking.