Once you've published your web application, you can edit it by clicking switch to builder mode.
Your story map should have similar options displayed. Under application configuration click settings. Choose the data tab. You can see that the choices correspond to the headers of your spreadsheet. This controls what information is displayed to the viewer. Make sure that the name and caption drop-down menus are set to name and description.
The Application settings menu also controls the layout design of your map. Explore the other tabs to refine your map and make sure to save your progress.
Every map needs a catchy title and description. You can edit yours by clicking on the pencil icon.
If you need to add a new tour point to your map, it's easy. On the bottom of the builder mode page, click add. You'll want to fill out this information in the same way you filled out your spreadsheet. Make sure that you have clicked and selected the last tour point in your data set. If you fail to do this, you may accidently save over an existing tour point with a new one.