There's more to becoming a writer than what you put on the page. Here are some tips I've discovered over the years. I think they can apply to all artists, really.
1. Get the highest level of education possible.
It will provide you with the most options.
2. Don't rely on your art to support you. Get a day job you don't hate.
Even if you have early success, keep something steady going just in case.
3. Keep your overhead low.
4. Prioritize your creative work above everything except health, family, friends and basic income.
5. Read the greats.
6. Relieve stress through daily exercise.
Sitting in a chair is rough on the body, mind and soul!
7. Rest, restore, recharge.
Yoga, meditation, naps, walks on the beach.
8. Build community.
Writing can be lonely. It's essential to surround yourself with people who understand. When you're feeling low, help someone else. Find a mentor and become one to someone else.
9. Develop an online presence.
Blog about what you're obsessed with; use Twitter to promote your friends' work; connect to your readers on Facebook; use Pinterest and Instagram for visual inspiration.
10. Don't read online reviews of your work.
11. Do It Yourself...
Even if you get a lucrative contract with a big publisher, you'll need to do a lot of the publicity and marketing yourself. Learn about all aspects of publishing. Attend conventions and conferences, panels and seminars. Network but in a genuine way about what you love with people who truly interest you.
12. ...But don't do it alone. Find creative allies to collaborate with. This will fulfill you creatively and psychologically and is essential in a competitive world.
I wish you the very best in your endeavors.