Here's the simplest rule for spotting when you’re "showing, not telling" that actually works:
Only write what your main character can sense with their five senses, right now, in that moment.
What do they see, hear, smell, taste, touch? What are their muscles doing in response? How does their breathing change?
Thoughts and emotions? Only if they're reacting to something they're physically experiencing. The smell of burnt toast triggering a memory. The sound of footsteps making their heart race. Then show that reaction and move on; the likelihood is your reader is already experiencing it.
Everything else — the backstory, the analysis, the clever observations — is telling in disguise.
I've just spent weeks rewriting my manuscript and I’m still slipping into telling in places. When you’re in narrator mode, explaining things instead of letting readers feel them is hard to spot. It's such an easy trap when you're in flow, when the words are pouring out and you think you're being brilliantly insightful.
But readers don't want your insights. They want to live the moment themselves. They want to clutch their fists in fear or cringe back in their seat with embarrassment.
The constraint is liberating. When you can only work with the physical world, every detail becomes intentional. Every sensation carries weight.
What moment in your story could you rewrite using only what the character's body knows?