Props are the objects that matter to your story and appear more than once: a magic wand, a well-loved teddy, a red balloon, a special key. Saving them as props keeps them looking the same every time they appear.
How props work
A prop lives in your World, next to your cast and settings. You give it a name and a description, and reference pictures (uploaded or generated, keeping the ones you like). From then on, the prop can be brought into your illustrations with the same shape, colour, and character every time.
When to make something a prop
Not every object needs to be a prop. Reach for one when an object is important and recurring, and when it would break the spell if it changed. If the teddy is the whole heart of the story, make it a prop so its stitched smile stays exactly the same from the first page to the last. A one-time background object does not need this.
How props reach the page
Like your cast and settings, props are pulled into illustrations through the World. Because they carry their own references, a prop stays on-model without you re-describing it each time. And like everything else, props follow the same guidance in reference pictures, explained.