John Steinbeck says

It is usual that the moment you write for publication -- I mean one of course -- one stiffens in exactly the same way one does when one is being photographed. The simplest way to overcome this is to write it to someone… Write it as a letter aimed at one person. This removes the vague terror of addressing the large and faceless audience and it also, you will find, will give a sense of freedom and a lack of self-consciousness.... Forget your generalized audience. In the first place, the nameless, faceless audience will scare you to death and in the second place, unlike the theater, it doesn’t exist. In writing, your audience is one single reader. I have found that sometimes it helps to pick out one person -- a real person you know, or an imagined person and write to that one.

 

Abandon the idea that you are ever going to finish. Lose track of the 400 pages and write just one page for each day, it helps. Then when it gets finished, you are always surprised.

Write freely and as rapidly as possible and throw the whole thing on paper. Never correct or rewrite until the whole thing is down. Rewrite in process is usually found to be an excuse for not going on. It also interferes with flow and rhythm which can only come from a kind of unconscious association with the material.

If a scene or a section gets the better of you and you still think you want it -- bypass it and go on. When you have finished the whole you can come back to it and then you may find that the reason it gave trouble is because it didn’t belong there.

Beware of a scene that becomes too dear to you, dearer than the rest. It will usually be found that it is out of drawing.

If you are using dialogue -- say it aloud as you write it. Only then will it have the sound of speech.

I hear via a couple of attractive grapevines that you are having trouble writing. God! I know this feeling so well. I think it is never coming back -- but it does -- one morning, there it is again..... Write poetry -- not for selling -- not even for seeing -- poetry to throw away. For poetry is the mathematics of writing and closely kin to music. And it is also the best therapy because sometimes the troubles come tumbling out.