Where would I begin to explain how to finish someone's first book? After all, everyone's writing method is a little different.
But I will not be scared off by this. No. I'm made out of sterner stuff.
The first bit of advice I can give you is this:
|Get THIS muse.|
If your story sucks and you find it isn't worth your time, leave it alone and start something else. But don't do that forever. At some point, something will be worth your time and when the going gets tough, you have to keep going.
All the way.
For as long as it takes.
Then... I strongly suggest that you play around until you find a method that works for you. Feel like plotting kills your story's soul, try pantsing. Think that waiting for your muse sucks, try enticing her/him with cookies. Whatever works. As long as you write. Except in limited circumstances, procrastination is never a good idea.
But if you block, and writing through it doesn't work, leave your project alone until the doldrums go away. If they don't, go back to your writing desk and write nonsense until they do.
For the love of all that is holy, DON'T write to trends. Trends change before you can publish. And if you're writing without passion, you won't produce anything good enough to change the trends back again.
Finally: Never be afraid to explore an idea, even if you think it's small or stupid. Because that idea might just be the right one that stirs enough passion for you to want to stick through the story.
What does it take for you to finish your story?