Diary methods:

In this type of research, the subjects of the case study are asked to keep a diary or record to which the researcher has access, either periodically or at the end of the study. The diary may be just a record of events, or include thoughts and emotions too, and may range from being completely unstructured to a set of responses to specified questions. A diary places a great deal of responsibility on the participants to complete it regularly and thoroughly, and to decide what will be of use to the researcher. If you are planning to use diary methods for your dissertation, you may therefore wish to combine them with other means of gathering data, such as direct observation, to cross-check what has been recorded.