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Freewrites are definitely great.
One thing I do after freewriting is to create a flowchart for my story.

I know where it begins, and I know where it's supposed to end.
All I have to do is connect the dots.

Quick tip to get out of writing agony

Don't write and edit and the same time. These two activities use different parts of your brain.

If you do both, it'll slow you down and you might get frustrated while seeking for perfection.