So let's begin!
Your tenth-grade creative writing teacher probably told you to outline everything before you start writing. I disagree. For me, this would never work. There has to be a certain amount of spontaneity involved to keep it fresh and interesting. If you can easily plot out the chapters and figure out the ending before getting past chapter one, chances are your reader will too. Remember, readers are very savvy and automatically try to figure things out as soon as they pick up a book. If you have no idea what is going to happen until you're typing it, chances are they will be just as surprised.
Not to say you shouldn't jot down ideas but I wouldn't bother organizing right away. You can picture specific scenes, conversations, events and know they're going to fit in somewhere, you just don't have to know where yet. Also, you must follow the natural flow of the story and take the characters into consideration; how will each action affect them? What is their own unique path or struggle? How does it fit in with the rest of the story?
Of course, I'm talking about fiction but what about non-fiction? Are the rules the same?
I probably would have an outline for something that falls under non-fiction, but with room to breathe so that you can see how the story flows and which angle it takes. Make sure it is factual and be ready to list any sources you might be using. Remember, you don't want to get sued.
Regardless of what you write, the first draft should be fun. Editing is another story. Let's not go there today. ☺️