To communicate. If a picture is worth a thousand words, a prototype is worth a thousand pictures.

To start a conversation. Your interactions with users are often ten times richer when centered around a conversation piece. A prototype is an opportunity to have another, directed conversation with a user.

To test possibilities. Staying low-res allows you to pursue many different ideas without committing to a direction too early on.

To manage the solution-building process. Identifying a variable also encourages you to break a large problem down into smaller, testable chunks.

To fail quickly and cheaply. Committing as few resources as possible to each idea means less time and money invested up front.

Start building. Even if you aren’t sure what you’re doing, the act of picking up some materials will be enough to keep you going.

Don’t spend too long on one prototype. Let go before you find yourself being too emotionally attached to any one prototype.

Identify a variable. Identify what’s being tested with each prototype. A prototype should answer a particular question when tested.

Build with the user in mind. What do you hope to test with the user? What sorts of behaviour do you expect? Asking these questions may help focus your prototyping and help you receive meaningful feedback in the testing stage.

Through testing, we can observe how to user reacts to the prototype, and learn more and empathise with the user.

Testing reveals if our prototype meets the user needs, and allows us to refine our point of view or reframe the problem.

Show, don’t tell. Put your prototype in the tester’s hands, or put your tester within an experience. Don’t explain everything yet. Give the minimal context so they understand what to do. Don’t explain your thinking or reasoning for your prototype. Let your tester interpret the prototype.

Have them talk through their experiences. For example, when appropriate, ask “tell me what you are thinking when you are doing this.”

Actively observe. Watch how they use (and misuse!) what you have given them, how they handle and interact with it. Don’t immediately “correct” what your tester is doing.

Follow up with questions. Listen to what they say about it and the questions they have. “Show me why this would (not) work for you.” “Can you tell me more about how this made you feel?” “Why?” “What do you think this button does?”