Getting set up with materials

You'll need a set of index cards or papers cut to about index-card size. You will also need a few Sharpie markers and a table with plenty of open space. Be prepared to spread out.

The steps

1. Find someone unfamiliar with your project to spend a few minutes — really, like five minutes — to help test your assumptions.
2. Write facets of an idea or product onto each card. Ideally you should have 30–40 cards like “voyages,” “hotels” and “car rental.”
3. Shuffle the cards. Providing them in order defeats the purpose. 
4. Then ask your volunteer to organize cards as they see fit.

Actually, that last step comes in two varieties: open and closed.

Open sorting: The first type, you simply have your tester organize cards into categories of their own creation. The results of this open-ended exercise will challenge may surprise you.

Closed sorting: In this exercise, you ask your testers to sort cards into the categories you provide. This helps balance a pre-defined website structure with users' expectations.

For example, one of our clients, a travel company, wanted to have travel packages, charters, about and lifestyle as their site's top-level navigation items. Other pages included testimonials, spa, legal disclaimer, etc. We suspected many people would want to know about travel arrangements — specifically, transportation and guides. Under which nav item would they look?

We used closed card sorting to find out. Most of our test subjects said "charters." A few asked, "why not just transportation?"

Open or closed, card sorting helps you understand your site from users' points of view. This gives you a good idea of how to organize your navigation in a natural way.

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