Asking users to log their activities, thoughts, and pain points throughout the work day. Asking users to record what they’re looking for, why, and whether they found it every time they execute a search.
Diary studies are really versatile and can be used either generatively when you are trying to understand a problem or when you are evaluating a design, such as during a beta test or even post-launch. Depending on how structured the questions or prompts are, diary studies can also provide some valuable tallies (e.g. None of our eight diary participants did [x]).
You want to better understand user actions, experience, and sentiment over time, ranging from a few days to a month or even longer.