Is it easy for the user to find the items or products they are looking for?
Are the categories meaningful?
Should an alternative approach to categories, sorting and filtering be used?
Write down the different shop items and shop categories on small notes, and let test participants sort the notes into what they thik is a fitting category.
Observe the test participants while they go through the different shop categories, guide them, and ask questions that identifies the test participants thoughts.
- On Usability.gov (old, tried and true): https://www.usability.gov/how-to-and-tools/methods/card-sorting.html
- Another great and in-depth guide: http://boxesandarrows.com/card-sorting-a-definitive-guide/
The art of interviewing:
- https://www.nngroup.com/articles/interviewing-users/Nielsen Norman Group:
- Another lovely guide: https://www.interaction-design.org/literature/article/how-to-conduct-user-interviews