Tip one: Be inspired. Don't write a book because you feel like you have to. If you set the goal "I want to write a book" without knowing what you want it to be about, you'll exhaust your mind struggling to come up with the perfect story before you've even begun.

Tip two: Know your plot. It's great to think up worlds and characters, and maybe even a conflict, but if you don't know where you want to take them, your beautiful world and interesting characters have nowhere to go.

Tip three: Don't get hung up on "finishing it." If you finish, you finish, if you don't, you don't.

Tip four: It doesn't have to be Walden. It doesn't even have to be The Tell-Tale Heart. It could be a novella, or even a short story. The idea shapes the form it takes. Your plot could even be told via epic poetry.

The most important thing about novel writing, playwriting, and short-story writing is that you can lean in amongst a group of people and say, "I have a story to tell." This is the craft of telling stories. Write out your rough draft. Rearrange plot points. Take plot points out that you feel are in fact superfluous. Take characters out that you realize have no real purpose. Add characters in, if you need them to do something specific in a scene.

When this becomes too heavy, put the draft in a drawer and don't look at it for at least a month. Then come back to it with fresh eyes, reread it, and see what you feel needs rearranging.

I write my own storys.Cinder is totally right about you don't have to finish anything. Something I want to say to add to that is when you write a story like the story. I wrote like 2 stories that I like until I got to a part that I hated and just droped the story. There's one other thing I want to add know what you are writing about. If that means you have to research a subject. Do because there are going to be people that could read you story and no the subject better. Good Luck writing.
PS None of my stories have I ever published so don't ask if they have been.