Gemma - Demo Content
Importing demo data (posts, pages, images, Customizer settings, etc.) is the quickest and easiest way to set up your new theme. It allows you to see how the theme works and if edit the demo content instead of creating everything from scratch.
After installing the Gemma theme and the recommended plugins, go to Appearance > Import Demo Data.
Click the Import Demo Data button.
On the next screen, you can ignore the plugin recommendations and click the Continue & Import button.
When the process is finished you will see a message that says "Import Complete!".