Choose an image linked to a central concern. Reintroduce it at meaningful turning points with changed context. A motif gains depth when recurrence lets the reader compare what the image means at different stages.
Worked example
A closed gate may first suggest exclusion, later protection, and finally a boundary the character chooses to open. The repeated image connects scenes while its meaning changes.
Three Appearances of a Key
At the start, Sera keeps the workshop key hidden because only she is allowed inside. Midway through the story, she cannot repair a machine alone and reluctantly lends the key to a collaborator. At the end, she places it on a shared hook beside the door. The writer wants the key motif to trace a change from control toward trust.