My tip to improve your typing speed is to... Practice and don't get stressed over improving your speed.

When my fingers hurt after too much time on the keyboard, I... ignore them and continue. I'm used to using a laptop and using my hands a lot so they don't get sore that often.

What really helped me improve my typing speed is... I stared writing stories for the fun. I could never type good in school because I was under a lot of stress to "be the best" at typing by everyone so when I started writing stories I didn't have any stress. I gradually became a lot fast at typing and I can actually find the right keys without having my eye's glued to the keys.