Written Tutorial
This tutorial by Esri's StoryMaps team is built in a StoryMap and provides helpful visual explanations demonstrating how to create a StoryMap, add basic types of content, add more advanced immersive content like the sidebar block and digital maps, configure your header and theme, and publish and share your story.
Video Tutorial
This 12-/14 minute video tutorial by Esri Ireland demonstrates how to create and style a StoryMap, add content to your story using content blocks, and how to work with some of the more advanced interactive content blocks including the sidecar block map tour block.