Diary studies can be used to record experiences, thoughts and activities over a period of time. It brings you as close as possible to your participants, without you actually being there.
Diary studies can be paper or electronic. Mobile and online tools have the advantage that you can examine the data as it is recorded, although paper diaries are sometimes better suited to the study. You should also ask your participants to take photos or videos to augment their diary entries.
Begin the study with an interview. This will allow you to explain the diary tool and make it clear what you want them to record. It will also give you the chance to get an understanding of their preconceptions and discuss their expected behaviour. Ensure the participant has a point of contact in case they are unsure of anything during the study.
At the end of the study, conduct another interview. Ask them to walk you through their diary entries and ask lots of open questions. Look for differences between what they thought they would do and what actually happened. Examine how their perceptions changed from beginning to end.