The personas are used to help the design team create a strong focus on the users [1]. Personas provide a common ground for the design team when communication about the design. Decisions about the design can be justified and explained based on the personas [1].

The number of characters should be between 3 and 6 [1]. By making more than one persona, a whole range of behaviour is covered. However, in order to keep the number of personas to a minimum and thereby make them more powerful, the behaviour of the personas should not overlap. The created personas are specific for a specific domain and can not be reused for another design problem. [2]

Relevant and interesting data can be cut out from the findings from the studies. These bits of data can then be sorted into groups in an "affinity" session. [1]

A central "foundation" can be used for each persona. This could be a document that holds all information about that specific persona (e.g. key attributes, goals, fears, typical activities, photos, reference material) [1]. The description of the persona should be no longer than 2 pages and focus on goals, skills, attitudes, and environment. No more than a few personal details should be added in order to give the persona personality but not to be in the way [2].

[1] Pruit, J. & Grundin, J. (2003). Personas: Practice and Theory. Proceedings of the 2003 conference on Designing for user experiences.
[2] Blomkvist, S. (2002). Personas - an overview. Departement of Information Technology, Human-Computer Interaction, Uppsala Universitet.