Some of us are picky choosy writers and we don't want to write unless it is perfect. Hogwash, I say. Put the story down, create the skeleton of it, the frame. More ideas will come and when you are feeling the urging, you will go back and fill in the blanks, revise and pull in the colorful words that captivate.
The other day I wrote an entire chapter in my new collection and yes, it took hours, but this included going back time and again and scratching, adding, flowering the words, doing more research. Read it aloud to yourself, it will be then you know to eliminate or accentuate.
I think the big advice is never doubt yourself. You are wearing a crown when you pen your thoughts, when you develop a story line, when you flower a word. You are all part of the greatness of your own Creation from the greatest Creation of all. God bless and just write.