Find an audio clip that relates to your story. Maybe it’s the sound of a train, or crickets, or rain falling on a sidewalk (YouTube is a good resource for this). Play the clip for about one minute before you begin writing. What rhythms do you hear? What metaphors can you pull out of the sound? What kind of atmosphere does the sound create? Wistful? Frustrating? Intense?
… and GO! Play the clip on repeat for 5 minutes while you write.