Presets

Presets or Prebuilt layouts allow you to seamlessly create page layouts by selecting from any prebuilt layouts included in your theme (If your theme has its own prebuilt layouts).

When editing a new page, you can choose a preset or create a layout from scratch by adding blocks. 

Open

Clicking on the Load preset near the layout you wish to use will bring up an important confirmation dialogue, indicating that any existing content will be overwritten by the prebuilt layout you have selected. Click OK to continue.