Develop an interesting story that your readers will like, and that you will enjoy telling.
Have at least one likeable character, and preferably several.
Villains can be likeable.
Show, don’t tell.
Avoid lazy words.
Make a general plan and fix it up as you go.
Set up scenes in advance. Put objects and people and clues in place, before they are needed.
When you are having trouble writing a scene, ask yourself if you need to go back in the story and set up the scene.
Spend time on research, and accumulate a research library built with real books. Put the library in your office near your desk.
Get an authoritative, prescriptive dictionary. You will need to do some hunting to find a good one, since most are out of print. Mine is a Webster’s New International Second Edition from 1938. You can find them on eBay or Abebooks or the like. Dictionaries have personalities. Find one that feels right to you.
Read, a lot. Read books and stories that bring you real pleasure.
Read stories published before the internet came along, and stories published after, and think about the differences between them. Which do you like more? Which will your readers like more? To this reader, stories in the age of the internet seem anxious, self-conscious, and less fun. You’re gonna have your own opinion about that, of course.
Write every day, when your mind is fresh. Mostly that means early morning. Get up, get some coffee, go to your office, get to work.
Take care of yourself; get your sleep, eat right, get some exercise, get a little sun. Do not neglect your family and friends, or you will regret it later.
Don’t get too concerned about being a writer or a poet or an artist. Don’t worry about being smart. Instead, read as much as you can, and do your research, and make a good plan, and let your characters tell your story for you.
The reader is smarter than you think. The reader can tell when you’re anxious, and when you’re having a good time.
Be aware of the Bechdel test. Look it up, if you don’t know what it is. Consider how your story might be improved if you applied Bechdel.
Read stories to children.
Ride the bus sometimes and listen to the people.