It's not easy to create a good set of personas to be used in your design effort. It takes research skills to determine who to talk to, what to explore, and then determine how to best represent the information in a set of personas. The smaller the set of personas, the easier it is for an organization to adopt and use. However, it's hard to get all of the information you need into a small set.
My blog post All Personas aren't Created Equal discusses what good personas should include, and this post includes a little more about how to get the data you need to create the personas.
How do you decide who to talk to?
Most importantly, you need to collect a good, thorough set of user data. You want to understand 1. The breadth of tasks and behaviors and 2. The most important tasks and behaviors to address with your product design.
In order to get at the breadth, the team must consider the differentiating characteristics that result in the most different kinds of behaviors. While the tasks themselves are not yet fully understood, the team can make an educated guess about differentiating characteristics.
What is the best way to gather the data?
The research team develops a set of open ended questions or inquiries to prompt discussion in the interviews or contextual inquiry. During the discussions, additional differentiating characteristics are often discovered, and tracked for recruiting and subsequent interviews.
The researcher looks for the broad range of tasks, and is skilled at digging in "deep enough" but not too deep. The researcher makes sure enough topics are covered within each segment (typically about four users for each topic). Researchers also listen for signs of top tasks and most important use cases to support.
How do I turn that data into a set of personas?
Once you've gathered information about users through interviews, you need to decide how many personas to create. Determining the right set and how to spread your data across them is tricky. My favorite method is to consider the differentiating characteristics again, and assign each characteristic to a persona. Put as many characteristics (and the supporting tasks) into a persona as possible, while keeping them "believable." Often times the characteristics and tasks can be spread across three "believable" personas; sometimes you need more depending on the nature of your business.
When you have the straw man set of personas with the differentiating characteristics, you can fold in the associated tasks, motivations, and notes about the context in which they do things (and other artifacts used). Give them a name, quote, and photo to make them more human and to help others have empathy for them as users of your products.
Understanding what makes a good persona is the first step, then actually doing it is the next step. It's a bit of an art and a science. And truth be told, you are probably wise to outsource the creation of a solid set of personas that your internal team can evolve as your products and user needs and behaviors do.
About the Author
Mary Piontkowski is a user experience specialist who has worked with high-profile companies such as Adaptive Path, Organic, and Macromedia. Through her strategic approach, creative expertise, and mastery of a variety methods for design and innovation, Mary has helped build robust experiences for Fortune 100 and 500 companies such as Macy's, Levi's, PayPal, Sun Microsystems, Hasbro, Sprint, Allstate, and Microsoft. "I'm a strategic design leader who thrives in ambiguity -- situations that require change and transformation. My defining work revolves around digital experiences. I believe good design and innovation come from collaboration between cross functional teams and through close attention to user insights, business goals, and some instinct. I find that strong leadership requires a mix of soft and hard skills, from emotional intelligence and adaptable communication to strong facilitation and persuasion skills. I understand that the context of a situation must be understood in order to ultimately have influence within an organization and with end users alike. I believe in adhering to standards, but am always looking for opportunities for invention. While I am strongest in a leadership role, I believe that design leaders should always stay involved with the creative process."