A storyboard is a visual tool to show user interactions as a story on a panel sequence. Each storyboard represents a different persona and scenario, and every panel has notes or descriptions to give more information on the story. Designers use a storyboard to help visualise a user journey and deliver a better, more user-centred product.
Storyboards are considered an informal tool, but they are helpful for designers and other stakeholders. As was mentioned, a storyboard can help visualise the user journey. The design team can notice potential pain points while working on or determine them after looking at a finished board and make necessary improvements to the user experience. This makes iterating design ideas faster and cheaper as many issues can be noticed and solved immediately. Creating a storyboard also requires empathy and putting oneself into the user's shoes. When designers make them, they can see the product through the user's eyes and adjust it better to their needs. Finally, storyboards are invaluable in communicating the design and user path to stakeholders not involved in technology or UX design.
Making a helpful storyboard means keeping it simple. Storyboards should be easily understandable, so keep the illustrations and notes simple. While you want the storyboard to convey a message mainly to the design team and other stakeholders, you should focus on the user while making them. Storyboards are about the users – they should reflect their perspective, needs, goals, and pain points to be effective as a tool. You should also iterate created storyboards and adjust them as needed. Gather feedback from other team members and stakeholders. Experiment a little to see how different choices or personas can be impacted by design. Then, enhance your storyboard so that your designs meet user needs and stakeholders' requirements.
Remember that even if storyboards are informal, you should still steer clear of making them based mainly on your assumptions. Take the findings from UX research and make sure that your storyboards are data-driven, not based on assumptions.
A storyboard is helpful both as a visualisation and a communication tool. It may be just a depiction of a potential user's experience and an informal way of showing the user journey, but it may also be what your team and stakeholders need to build a successful product.