Published author here. Some advice I can pass on to others.
- Do a lot of reading and examine how characters are developed.
- Do a lot of writing. Keep refining your craft.
- Write multiple drafts. In most cases, you should write the first draft with “the door closed” meaning only you look at that draft. The second draft is with “the door open” when you have others review it to give feedback about characters and whether their motivations make sense.
- Be prepared to do a lot of editing before you submit a final draft for agents or publishers to consider. Independent publishers don’t require agents but major publishers do.
- Work on your pitch for your writing. That means you need a short description of your writing that gets people interested.
- Remember that you won’t get immediate acceptance. You will be rejected. But if you keep at it, you will find somebody who will take a chance on you.
- Have fun.