Follow the repeated work.
Look for a task with clear inputs, predictable steps, and a result you can check. Moving information between systems or preparing a document can be a more useful starting point than a broad assistant.
Keep people in the loop.
Set a review step for decisions that need judgement. Make it easy to understand what changed, correct an error, and return to a manual process.
Measure the whole workflow.
Count review time and exceptions as well as time saved. A small, dependable improvement is a better foundation than a demonstration that only works under ideal conditions.