There is no substitute for writing. 
Start small. Write a good sentence, then a good paragraph. Write a lot. You might not be great from the start, but it is the road to good writing.

Writing is about thinking, researching, contemplating, outlining, composing, then maybe some typing with revisions as you go, deletions, additions, reflections, setting aside and returning afresh.
Typing is what you do in the middle of the two vast thoughtful processes.

Read good writing—Dickens or Baldwin or evolutionary biology textbooks or the Old Testament, whatever holds your attention.

Don't read something just because it is popular at the moment; otherwise, you will be like everyone else and will not be able to make a meaningful contribution.

Feedback is great, but there are times when you know exactly what you're doing. Listen to what makes you move or stops you in your tracks.
Listen to your own feedback and realize that you move forward through mistakes and flawed but aspiring work. Write for other people, but don't take their feedback to seriously.

Talent is overrated. You need passion, vocation, vision, and dedication to get you through the rough spots in your style.

Writing takes time. It means you will need to find that time. 

You probably have to do something else for a living in the beginning, but don't develop expensive habits or consume hobbies that will prevent you from writing.

Always get your facts right. Don't misrepresent. 

Regardless of what you're writing about, you have an obligation to get it right. Your credibility rests on your accuracy.

Writing is facing your deepest fears and failures, hoping that your worst version is revised so that posterity will never know how awful it was.

In there, your work has to bring you some kind of joy, including the joy of hard truths, told honestly. Find pleasure and joy. How you feel is something that you cannot take too seriously. Doing something is a means of not being stuck in how you feel.

Success is very nice, but it is not love. It is at best the result of love of the work, but not of you.

Producing art is the process of becoming a person with independent thought, a producer of meaning, not a consumer of meanings that may be at odds with your inner person.

It's up to you to become a good writer and you probably already know everything else you need to know, somewhere underneath the noise and the anxiety and the outside instructions.