Perhaps an artist or a performer. They often need to step into a confident state before presenting their work or sharing their creative stories. By saying 'put on my crown and tell the story', they are psyching themselves up, getting into the right mindset where they feel like they are in a position of power and can captivate their audience with their story. It could also be someone who has overcome a great deal in life and now wants to tell their inspiring story. They use this phrase as a way to remind themselves of their strength and worthiness to be heard.
Maybe someone who has had a long and eventful journey. They put on their robe, which could be a reminder of their travels, and then start to tell their story. It could be a way for them to create a certain atmosphere, both for themselves and for the listeners.
It could be anyone really. A person who has a collection of interesting stories and likes to be in a relaxed state when sharing them. For instance, a traveler who has had many adventures and likes to put on a cozy robe in their living room after a long journey and then tell their travel stories to friends or family. Or it could be a teacher who wants to make the story - telling session more engaging for students by creating a bit of a theatrical element with the robe - wearing and then sharing a historical or literary story.
It could mean to assume a position of confidence or authority (the crown representing a sense of self - importance or leadership) and then share a story. Maybe it's about someone getting into a state of mind where they feel empowered to tell their tale.
Dylann Roof is a white supremacist mass murderer. He likely said 'tell my story' in an attempt to spread his hateful ideology. His actions were despicable and his 'story' is not something that should be glorified.
A female writer who has a unique perspective on women's issues might say this. She may feel that men, due to their different life experiences, cannot accurately represent the stories of women.
Someone who has just had a harrowing experience, such as a survivor of a natural disaster.
One reason could be for the sake of honesty. They want to present a full picture that includes both their own side and another's.
A witness to a crime who was in danger during the incident. For example, if someone witnessed a violent robbery and was almost hurt by the criminals, but managed to escape unharmed. They are alive to tell the story of what they saw and help the police in their investigation.
It could be that their story involves something that they think others won't understand or believe. For example, if it's a very strange or personal spiritual experience. Also, perhaps they've been through something that is so unique and difficult to put into words that they don't want to even attempt to tell it, as they are worried about not being able to convey it accurately and having people misinterpret it.
It could be that the robe is a family heirloom or has some special significance. Wearing it gives them a sense of connection to the past and the stories that have been told before, and it makes the current story - telling more special. It might also be really comfortable, and when they are comfortable, they can better focus on telling the story.