How Do We Turn an Idea Into a Story?

i know some people struggle with ideas, but let's assume people have lots of ideas. How can we flesh an idea into a story? And also, how do we know what that story is? One thing that works really well for me is can a free writing about it, or journalling on it. Another thing that i've been experimenting with lately is using terro cards. That was partly inspired by your podcast with caroline donahue. It was for afew years back. So those are two tools that i tend to use when it comes to flashing out an idea.