RSRohan Sandeep

Functional foundation · Field guide

Prototyping

Build the smallest representation that can answer the next important question.

What the field is

A prototype is a learning instrument. Its fidelity should match the uncertainty: a sketch can test structure, a clickable flow can test sequence, and a coded or Wizard-of-Oz prototype can test behaviour that static screens cannot represent.

Methods

Ways to practise the skill.

Choose methods because they reduce the uncertainty in front of the team—not because a template says they belong in the process.

01

Paper or sketch prototype

Create disposable representations to explore structure and alternatives quickly.

Helpful whenThe team needs breadth and should not become attached to polish.
02

Clickable flow

Connect key screens with realistic tasks, states, and content.

Helpful whenTesting navigation, comprehension, or sequence.
03

Wizard of Oz

Simulate complex or automated behaviour manually while the participant experiences a working facade.

Helpful whenTesting value and interaction before expensive automation exists.
04

Technical spike

Build a narrow coded experiment to test feasibility, latency, data, or integration risk.

Helpful whenThe most consequential uncertainty is technical rather than visual.
Useful links

Continue into the field.

Practical standards and method guidance from established sources.

Design KitPrototyping plan templateGOV.UK Service ManualMaking prototypes