A list of things that work for me personally as a writer, so it's worth reminding myself of them every time.
Most writing advice is 1) prescriptive and 2) much too rigid. I say, do whatever makes sense to you and results in a story people like. As long as you have fun writing, you're probably doing it right.
No, it's not magic, just how brains work: names breathe life into your creations, making them take shape in your mind. A good working title for example doesn't just make it easier to talk about your work in progress, but embodies its tone and themes, keeping them front and center.
It's fun to imagine detailed fictional worlds for the sake of it, but they don't make a story. Who cares what kind of stone is used in the bridges of your imaginary city? Tell me how the viewpoint character knows and why it matters to them, and we're getting somewhere.
That said, it's good to add details which suggest a larger world just out of frame. People coming and going. Changing weather. Vistas in the distance. You can't show everything, but the reader's imagination will do the rest.
On a related note: any new character, event or worldbuilding detail added to the story needs to grow out of something else that's already there, and remain rooted in it. That way there's no question if it belongs.
It's no fun adding characters to a scene only to realize pages later that only two of them say or do much at all. Remember to give everyone a couple of lines, and stage directions. Makes the scene more lively, too.
Speaking of which, if there are too many characters in your story to pull that off, there's a trick used mostly by playwrights: have characters move in and out of frame as needed, so as to keep their number manageable at any one time, and give them all a chance to shine instead of getting lost in a crowd.
You can't have high action all the time. That would either burn you out, or the reader. You can have page after page of descriptions, or dialog, but that's boring. Whatever you're doing right now with the story, break it up now and then. Mix it up. Keep the text fresh.
Some writers complain that beginnings are hard, but to me they seem the easiest part of a story. Perhaps because I think of them as seeds instead: the kernel from which a story sprouts. They don't even have to be in the beginning, strictly speaking.
It's tempting to take the high-level view as a writer, but it's also a common way to get stuck. Where do you even begin? When is it enough? Better come down to earth and only describe one place at one time.
Stories wouldn't be stories if they didn't invite audience participation. But in order to do that the storyteller must leave room for the audience's imagination. That means partly giving up ownership of the story. Excellent!
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