Read. Read read read as much as you can. Read young adult books. Read old adult books. Read kids’ books. Read as many books you can get your hands on. This way you collect words and phrases and you can see how the professionals do it. When you’re done, reread your favorites and even the books you like not as much. Trust me, reading will make things so much easier later on.
It also introduces you to books you might have never read otherwise. You might be recruited into new fandoms along the way. If you read how I’m telling you, writing won’t be The Easiest Thing in the world, but it certainly won’t be The Hardest Thing.
(Some of you might be shaking your heads at advice from a thirteen year old. Please note that I am young, not stupid. I may be younger than some of you, but please don’t judge me for it.)