Every time you read something outside your 'normal' genre, your comfort zone, you expand your mind just a bit.
You drop a new idea into the soup of your imagination, adding to the flavor.
You light a tiny flicker of something 'not quite right' into a dark part of your mind.
It's not always easy or fun. Some of the stuff you pick up will be utter piffle (a real word, look it up!) and will be filed away in your 'forget this' file cabinet.
But most of the stuff will add to your arsenal of things to explore. The more you read, the more you experience.
Pick up a high school biology book and just skim it, cover to cover. I bet you will remember less than I did! ;0) But didn't it spark a few ideas? I'll bet you had a dozen ideas for your books just by reading about DNA again! It sure sparked my imagination, it's in virtually everything I write now!
Read a genuine, old time western novel.
How about a, shudder, romance novel? Careful, these are addictive. ;-)
No matter what you pick up, study some of it. If it's fiction, get inside the author's head and see the story from his or her point of view. Keep going until you get SOMETHING that you've never thought of before.
Grab that idea. Swirl it around in your mouth, getting a taste of it. Feel the texture of it's
undercurrent; what makes THIS story so interesting to so many people?
Every thing you read and study will help grow your imagination. And that's where your stories come from.
Read. Study. Go!