Choose one assumption
Imagine an app helping students discover science. Is the difficulty finding content, understanding it or finishing it? Pick one assumption before drawing screens.
Test the journey on paper
Sketch three screens: start, choice and result. Ask someone to complete a specific task using the sketches. Observe hesitation and questions. A compliment is not evidence that the journey works.
Name the next decision
Review the observations and choose a revision, another test or a limited build. Record what this round did not test so a small prototype is not mistaken for validation of the whole venture.