Card sorting is a user-centered exercise which requires multiple users to group your content/pages into categories, and then label those categories.
What you'll need
Card sorting is a technique employed to ensure you have a user-centred approach to your Information Architecture (IA). It can make sure your site isn’t centred around your business processes and more in-line with your users mental models.
To make a validated and user-centric IA, you need a 2-tier approach to card-sorting; open and closed.
Open card sorting
Open card sorting consists of asking your users to categorise your content for you. You can use tools such as OptimalSort, or simply post-its if you’re doing it in-person.
Pick the pages that your ~25/30 top tasks are on, and once the users have categorised them, ask them to label the groups. This might spark some ideas for labelling and top-level navigation that you haven’t thought of. There are no constraints here, hence ‘open’ card-sorting. From this open sort, create a first draft of your IA using the user inputs from your first round of card sorting.
Closed card sorting
Using your entire top tasks list, ask users to sort these into your pre-determined top-level nav. This is why it is ‘closed’, we’re constraining the users into what categories they can put pages. This should give you a good idea into whether your top level IA is on the right path.
Note: You will never accommodate every users mental model of your site, but this process gives you a good chance of matching a majority.
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