Well, you just have to keep doing it . It was the same for me at the beginning but then I started to get along with it, now i type faster when i sing along with the song. Oh and I think it helps if you choose one song to play on repeat when u type, see if your speed increases after 10-15 listens!!

I tried this but I kept typing the words I was hearing lol

What really helped me improve my typing speed is music! Play music in the background and type as you sing along with it!! IT HELPS!!!!