Write now. Revise later.
Writers want their words to be perfect. But the words don’t usually begin that way. This can cause writer’s block and lead to frustration.
Sometimes the best thing to do is just write. Write with whatever mixed-up, nonsensical grammar it takes to put a story on paper. Because telling the story is the hardest part.
When you go back to revise your work, you’ll have complete ideas to work with. It won’t be as difficult to fix grammar and add depth because the backbone of the story is already there.