I’ve written on how to approach early drafts if you’re a discovery (pantser) writer. Be free. Take chances. Do lots of prewriting as you’re writing. Understand that because you don’t outline, you will almost certainly need several drafts. All right--so let’s say you’ve written three drafts. Remember, the first draft will be 10K-15K because you're finding your way. The second draft will probably be around 40K because you’re still finding your way and building on top of the foundation you’ve put down.
In draft 3, which might be your final draft, or/and draft 4—you’ll be trying to give your writing structure and development and theme and all the things that you need. You’ll be adding a words. How many depends on you.
When you get to a draft where you have discovered and given some detail to big moments in your novel, then you need to work in foreshadowing. Now, when you’re a reader, you think of foreshadowing as something that gives the reader a sense or clues as to what will happen. As a discovery writer, I’m suggesting you work backward from the important moments of your story and build the foreshadowing to them. Most of your story can be worked out this way.
Let’s say you have a few plots working in your novel—a mystery plot and relationship plot and a few others. One is the main plot and you have two or three subplots. Once you figure out where they end, you simply work back in a logical way to where they begin (of course it’s not simple or easy, but this will give you a kind of reverse map to follow). So if you have a relationship plot that ends with the girl getting two boys, then you have to figure out how this happened. You have to work with intention to build an exciting, interesting, logical sequence that will lead the reader to whatever ending you’ve worked out. That’s one strand of your story. Then you move on to the next. And next. And next.