A great persona must be shareable, and explains the big picture of your users
Before I explain how to make better personas, I'd like to define what a persona is. A persona is just a representation of the goals, fears, and behaviors of an actual group of users. Great personas allow team members and stakeholders to quickly empathize with their users. Being loyal to your users will make you users loyal to your business.
A great persona must be shareable. A shareable persona is a persona that can easily be distributed to team members, product owners and stakeholders. It allows for anyone to quickly remind themselves who they are building a product or service for.
Making your personas the size of a standard business card is a great way to make your personas shareable. This will allow team members and stakeholders to refer to to them whenever they need to on the go.
These sharable personas should always speak the vocabulary of the people holding them. Something is wrong with your personas if they can't be easily understood the first time they are viewed. Personas shouldn't evoke questions, they should provide answers and direction to future problem solving.
We don't want to get lost in the little details. Too much demographical information doesn't matter too much. A lot of the demographical information can be portrayed through the persona profile image. You should be able to tell their gender, age group right off the bat. Plus, an image can make a persona a lot more personal than words regarding their demographic.
By listing behaviors and goals we can start to make user conscious decisions about new features or visual designs. We then know how to prevent user frustration once we understand what makes our users stop in their tracks.
Personas should always be backed by research, whether it is qualitative or quantitative research. We are only making assumptions if we don't back our personas with research. And when we assume we only make an ASS of U and ME. Our assumptions could possibly be the opposite of the truth, and our false personas could be leading us into the path of user frustration and a lack of fulfillment.
If you're wondering where to start with research sources, you can start with the following list: