Style guides are typically client-generated. However, you can create your own if you think it will streamline your Storyline development. This can be especially important in team situations where multiple developers will be working on one project.
Style guides are documented explanations and illustrations of stylistic options available for the products in development. These stylistic options typically include approved logos and branding, colors (and corresponding hex values), appropriate fonts and sizes, and can even be so specific as to dictate the pixel width of a highlight box or the screen resolution the product must adhere to.
Basically, the style guide indicates how your story should look or feel and attempts to stay on brand, based on project specifications. Other elements may even include the tone of voice used or grammar preferences.
Using a style guide during your Storyline development can help streamline your development approach in terms of reducing rework. When...