Typing fast naturally means that you can get things done faster. When we are typing fast, we are not telling our brain to slow down so that our fingers can keep up to the slur of words your brain has produced.
Keeping up with the brain is a good way of maintaining high levels of productivity for longer.

Speed versus accuracy

Similar to what the above image is trying to make a joke of, the ability to type fast is useless if you are not typing the right things. It then begs the question, should I focus on typing fast or typing accurately?

Our fingers and the movements that we make on the keyboard subconsciously is what we call muscle memory. I attribute inaccuracy in typing to the lack of proper training for your keyboard muscle memory.
In other words, typing accurately is fundamental, and a prerequisite, to typing fast.

Practicing to type accurately

In a keyboard, there is something called the home row.
Briefly, the home row is where you would place your fingers, by default, before beginning to type.
From this home row where all your 8 fingers are placed, you will then start to move up and down to type the letters.
Ideally, each character on the keyboard should only have one finger assigned to it.
So then, which finger do I choose for each character?

Introducing TypingClub

TypingClub is a website that was created to teach you touch typing.
It basically means that you are typing without looking at the keyboard.
The sentence above alone proves that muscle memory is at work in having you reach out to the right characters at the right time of the word that you are currently typing out.

Typing Club has already thought and tested the best finger to use when typing each character that you see on your keyboard.
I would recommend that you use that website to practice/learn your touch typing at least 30 minutes each day.

I would also urge that you focus on being accurate rather than being fast.
The application will tell you the speed at which you are typing, pay no attention to this.
As I have explained earlier, it is more important to type accurately that it is to type fast.
With accuracy, it will then just take practice to get the speed up.
If you start out with speed without great accuracy, fixing that muscle memory is going to take some time.
You may have already lost so much productivity in the mean time.

Conclusion

We are in the digital age and with that comes some form of evolution from us humans. The interface at which we primarily adopt when speaking to our machines is through the keyboard and mouse.

As of this writing, the main method of typing is still on the keyboard and mouse and I foresee that this will be the case for the foreseeable future.
Invest in this essential skill like how you used to invest time in learning how to read and spell.
It is not about the speed at which you read but rather the accuracy of the pronunciation of the words that you are reading that forms the foundation of your communication prowess to the society around you.