Some people are good at listening to their gut instinct. They are the ones who claim to be very intuitive. They often can’t tell us why they made a particular choice, just that it “felt right”.
A lot of us are not so good at this. Yes, we have feelings, intuitions, but we don’t trust them, or we kind of trust them. We waver and second-guess ourselves. We have uneasy feelings, anxiety, and get into arguments with ourselves, belittle the intuition, try to force ourselves to be “logical” and “practical” to squelch down the uneasy feelings.
I think that listening to your gut isn't about anything specific to your stomach region. It's about reading your body as a whole. When you have a reaction – changes in heartbeat, breathing, and muscle tension – why did your body react in that way?

But most of us most of the time also have a million thoughts and preconceptions about the people we know and are inclined to pay attention to those thoughts, that knowledge, that experience, those memories.

In my story, FINDING JUNIPER, because Juniper has amnesia, she had no choice but to see people with new eyes. She couldn’t rely on her knowledge or past impressions of people who said they were her friends. She had no memory of them.

Because of this her senses were sharpened. She was tuning in to her physical reactions. She was relying on her instinct.
In writing FINDING JUNIPER, I found it an intriguing exercise to look at familiar objects and people and ask, “If I had never seen this situation, person, or thing before, what might I perceive?”